UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                    FORM 10-Q


[X]  Quarterly Report Pursuant to Section 13 or 15(d) of the Securities
     Exchange Act of 1934

For the quarterly period ended September 30, 1999

                                       or

[ ]  Transition Report Pursuant to Section 13 or 15(d) of the Securities
     Exchange Act of 1934

For the transition period from _______________ to _______________

Commission File Number 1-10709

                             PS BUSINESS PARKS, INC.
                             -----------------------
             (Exact name of registrant as specified in its charter)


          California                                        95-4300881
          ----------                                        ----------
  (State or Other Jurisdiction                           (I.R.S. Employer
       of Incorporation)                              Identification Number)


               701 Western Avenue, Glendale, California 91201-2397
               ---------------------------------------------------
               (Address of principal executive offices) (Zip Code)


       Registrant's telephone number, including area code: (818) 244-8080


Indicate by check mark whether the registrant (1) has filed all reports required
to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during
the  preceding 12 months (or for such  shorter  period that the  registrant  was
required  to file  such  reports)  and  (2)  has  been  subject  to such  filing
requirements for the past 90 days.

                                    Yes X  No
                                       ---   ---

Number of shares outstanding of each of the issuer's classes of common stock, as
of  November  10,  1999:
Common  Stock,  $0.01  par  value,  23,645,461 shares outstanding


                             PS BUSINESS PARKS, INC.

                                      INDEX


Page PART I. FINANCIAL INFORMATION

Item 1.   Financial Statements

          Condensed Consolidated Balance Sheets as of September 30, 1999
          and December 31, 1998.........................................       2

          Condensed Consolidated Statements of Income for the Three
          and Nine Months Ended September 30, 1999 and 1998.............       3

          Condensed Consolidated Statement of Shareholders' Equity for
          the Nine Months Ended September 30, 1999......................       4

          Condensed Consolidated Statements of Cash Flows for the Nine
          Months Ended September 30, 1999...............................  5 -  6

          Notes to Condensed Consolidated Financial Statements..........  7 - 16

Item 2.   Management's Discussion and Analysis of Financial Condition
          and Results of Operations..................................... 17 - 25

Item 3.   Quantitative and Qualitative Disclosures About Market Risk....      26

PART II.  OTHER INFORMATION

Item 1.   Legal Proceedings.............................................      27

Item 6.   Exhibits & Reports on Form 8-K................................      27



                             PS BUSINESS PARKS, INC.
                      CONDENSED CONSOLIDATED BALANCE SHEETS



                                                                           September 30,            December 31,
                                                                                1999                    1998
                                                                          ---------------         ---------------
                                                                            (unaudited)
                                                       ASSETS
                                                       ------
                                                                                            

Cash and cash equivalents...............................                  $   118,988,000         $     6,068,000

Real estate facilities, at cost:
   Land.................................................                      192,352,000             176,241,000
   Buildings and equipment..............................                      623,585,000             536,697,000
                                                                          ---------------         ---------------
                                                                              815,937,000             712,938,000
   Accumulated depreciation.............................                      (43,932,000)            (22,517,000)
                                                                          ---------------         ---------------
                                                                              772,005,000             690,421,000
Construction in progress................................                        7,137,000               7,716,000
                                                                          ---------------         ---------------
                                                                              779,142,000             698,137,000

Receivables.............................................                          295,000                 242,000
Deferred rent receivables...............................                        4,630,000               2,086,000
Intangible assets, net..................................                        1,357,000               1,583,000
Other assets............................................                        1,975,000               1,298,000
                                                                          ---------------         ---------------
              Total assets..............................                  $   906,387,000         $   709,414,000
                                                                          ===============         ===============


                                        LIABILITIES AND SHAREHOLDERS' EQUITY
                                        ------------------------------------

Accrued and other liabilities...........................                  $    19,210,000         $    15,953,000
Line of credit..........................................                                -              12,500,000
Mortgage notes payable..................................                       45,828,000              38,041,000
                                                                          ---------------         ---------------
         Total liabilities..............................                       65,038,000              66,494,000

Minority interests:
   Preferred units......................................                      132,750,000                       -
   Common units.........................................                      156,210,000             153,015,000

Shareholders' equity:
   Preferred stock, $0.01 par value, 50,000,000
     shares authorized, 2,200 shares issued and
     outstanding at September 30, 1999 (none
     issued and outstanding at December 31, 1998).......                       55,000,000                       -
   Common stock, $0.01 par value, 100,000,000
     shares authorized, 23,645,461 shares issued
     and outstanding at September 30, 1999
     (23,635,650 shares issued and outstanding at
     December 31, 1998).................................                          236,000                 236,000
   Paid-in capital......................................                      479,466,000             482,471,000
   Cumulative net income................................                       62,906,000              32,554,000
   Cumulative distributions.............................                      (45,219,000)            (25,356,000)
                                                                          ---------------         ---------------
         Total shareholders' equity.....................                      552,389,000             489,905,000
                                                                          ---------------         ---------------
            Total liabilities and shareholders'equity...                  $   906,387,000         $   709,414,000
                                                                          ===============         ===============


                             See accompanying notes.

                                       2


                             PS BUSINESS PARKS, INC.
                   CONDENSED CONSOLIDATED STATEMENTS OF INCOME
                                   (Unaudited)



                                                             For the three months                For the nine months
                                                              ended September 30,                ended September 30,
                                                        --------------------------------   --------------------------------
                                                             1999             1998              1999             1998
                                                        --------------    --------------   --------------    --------------
                                                                                                 

Revenues:
   Rental income.................................       $   32,568,000    $   25,635,000   $   92,544,000    $   61,459,000
   Facility management fees from affiliates......              121,000           109,000          351,000           440,000
   Interest and other income.....................              592,000           533,000          885,000         1,077,000
                                                        --------------    --------------   --------------    --------------
                                                            33,281,000        26,277,000       93,780,000        62,976,000
                                                        --------------    --------------   --------------    --------------
Expenses:
  Cost of operations.............................            8,920,000         7,379,000       25,951,000        18,361,000
  Cost of facility management....................               24,000            12,000           70,000            49,000
  Depreciation and amortization..................            7,594,000         4,865,000       21,641,000        11,421,000
  General and administrative.....................              742,000           593,000        2,339,000         1,589,000
  Interest expense...............................              977,000           667,000        2,658,000         1,736,000
                                                        --------------    --------------   --------------    --------------
                                                            18,257,000        13,516,000       52,659,000        33,156,000
                                                        --------------    --------------   --------------    --------------

Income before minority interest..................           15,024,000        12,761,000       41,121,000        29,820,000

  Minority interest in income - preferred units..           (1,022,000)                -       (1,236,000)                -
  Minority interest in income - common units.....           (3,347,000)       (3,013,000)      (9,533,000)       (8,696,000)
                                                        --------------    --------------   --------------    --------------
Net income.......................................       $   10,655,000    $    9,748,000   $   30,352,000    $   21,124,000
                                                        ==============    ==============   ==============    ==============
Net income allocation:
  Allocable to preferred shareholders............       $    1,272,000    $            -   $    2,134,000    $            -
  Allocable to common shareholders...............            9,383,000         9,748,000       28,218,000        21,124,000
                                                        --------------    --------------   --------------    --------------
                                                        $   10,655,000    $    9,748,000   $   30,352,000    $   21,124,000
                                                        ==============    ==============   ==============    ==============
Net income per common share:
  Basic..........................................       $         0.40    $         0.41   $         1.19    $         1.18
                                                        ==============    ==============   ==============    ==============
  Diluted........................................       $         0.40    $         0.41   $         1.19    $         1.17
                                                        ==============    ==============   ==============    ==============
Weighted average common shares outstanding:
  Basic..........................................           23,641,000        23,636,000       23,639,000        17,920,000
                                                        ==============    ==============   ==============    ==============
  Diluted........................................           23,724,000        23,696,000       23,713,000        17,990,000
                                                        ==============    ==============   ==============    ==============


                             See accompanying notes.

                                       3


                             PS BUSINESS PARKS, INC.
            CONDENSED CONSOLIDATED STATEMENT OF SHAREHOLDERS' EQUITY
                  For the nine months ended September 30, 1999
                                   (Unaudited)



                                                      Preferred Stock                   Common Stock
                                                 -----------------------------    ---------------------------
                                                    Shares           Amount           Shares         Amount
                                                 ------------    -------------    -----------    ------------
                                                                                     

Balances at December 31, 1998................               -    $           -     23,635,650    $    236,000

   Issuance of preferred stock, net of
     issuance costs..........................           2,200       55,000,000              -               -

   Issuance of common stock..................               -                -          9,811               -

   Net income................................               -                -              -               -

   Distributions paid:
       Preferred stock.......................               -                -              -               -
       Common stock..........................               -                -              -               -

   Adjustment to reflect minority interest
     to underlying ownership interest........               -                -              -               -
                                                 ------------    -------------    -----------    ------------
Balances at September 30, 1999...............           2,200    $  55,000,000     23,645,461    $    236,000
                                                 ============    =============    ===========    ============






                                                                      Cumulative        Cumulative         Shareholders'
                                                 Paid-in Capital      Net Income       Distributions          Equity
                                                 ---------------     -------------    ---------------     --------------
                                                                                              

Balances at December 31, 1998................    $   482,471,000     $  32,554,000    $   (25,356,000)    $  489,905,000

   Issuance of preferred stock, net of
     issuance costs..........................         (1,914,000)                -                  -         53,086,000

   Issuance of common stock..................            161,000                 -                  -            161,000

   Net income................................                  -        30,352,000                  -         30,352,000

   Distributions paid:
       Preferred stock.......................                  -                 -         (2,134,000)        (2,134,000)
       Common stock..........................                  -                 -        (17,729,000)       (17,729,000)

   Adjustment to reflect minority  interest
     to underlying ownership interest........         (1,252,000)                -                  -         (1,252,000)
                                                 ---------------     -------------    ---------------     --------------
Balances at September 30, 1999...............    $   479,466,000     $  62,906,000    $   (45,219,000)    $  552,389,000
                                                 ===============     =============    ===============     ==============

                             See accompanying notes.

                                       4



                             PS BUSINESS PARKS, INC.
                 CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                                   (Unaudited)





                                                                            For the nine months ended September 30,
                                                                          -----------------------------------------
                                                                                1999                       1998
                                                                          -----------------          --------------
                                                                                               

Cash flows from operating activities:
   Net income........................................................     $      30,352,000          $   21,124,000
   Adjustments to reconcile net income to net cash provided
   by operating activities:..........................................
       Depreciation and amortization expense.........................            21,641,000              11,421,000
       Minority interest in income...................................            10,769,000               8,696,000
       Increase in receivables and other assets......................            (3,274,000)             (2,620,000)
       Increase in accrued and other liabilities.....................             3,257,000               3,221,000
                                                                          -----------------          --------------
         Total adjustments...........................................            32,393,000              20,718,000
                                                                          -----------------          --------------

         Net cash provided by operating activities...................            62,745,000              41,842,000
                                                                          -----------------          --------------

Cash flows from investing activities:
       Acquisition of real estate facilities.........................           (59,555,000)           (252,649,000)
       Acquisition cost of business combination......................                     -                (424,000)
       Capital improvements to real estate facilities................           (10,546,000)             (6,030,000)
       Construction in progress......................................           (11,567,000)                      -
                                                                          -----------------          --------------
         Net cash used in investing activities.......................          ( 81,668,000)           (259,103,000)
                                                                          -----------------          --------------
Cash flows from financing activities:
       Borrowings from an affiliate..................................            41,400,000             179,000,000
       Repayment of borrowings from an affiliate.....................           (41,400,000)           (182,500,000)
       Borrowings from line of credit................................            14,000,000                       -
       Repayment of borrowings from line of credit...................           (26,500,000)                      -
       Principal payments on mortgage notes payable..................           (11,932,000)               (343,000)
       Net proceeds from the issuance of common stock................               161,000             272,112,000
       Net proceeds from the issuance of preferred stock.............            53,086,000                       -
       Net proceeds from the issuance of preferred operating
         partnership units...........................................           129,695,000                       -
       Distributions paid to preferred shareholders..................            (2,134,000)                      -
       Distributions paid to common shareholders.....................           (17,729,000)            (15,897,000)
       Distributions paid to minority interests - preferred..........            (1,236,000)                      -
       Distributions paid to minority interests - common.............            (5,568,000)             (6,248,000)
                                                                          -----------------          --------------

         Net cash provided by financing activities...................           131,843,000             246,124,000
                                                                          -----------------          --------------

Net increase in cash and cash equivalents............................           112,920,000              28,863,000

Cash and cash equivalents at the beginning of the period.............             6,068,000               3,884,000
                                                                          -----------------          --------------
Cash and cash equivalents at the end of the period...................     $     118,988,000          $   32,747,000
                                                                          =================          ==============


                             See accompanying notes.


                                       5


                             PS BUSINESS PARKS, INC.
                 CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS
                                   (Unaudited)



                                                                            For the nine months ended September 30,
                                                                            ---------------------------------------
                                                                                  1999                    1998
                                                                            ---------------           -------------
                                                                                                
Supplemental schedule of non-cash investing and financing activities:

Acquisitions  of real estate  facilities  and  associated  assets and
   liabilities in exchange for minority  interests and mortgage notes
   payable:
       Real estate facilities........................................       $   (20,752,000)          $ (33,584,000)
       Other assets (deposits on real estate acquisitions)...........                     -                 800,000
       Accrued and other liabilities.................................                     -               1,245,000
       Minority interest - common units..............................             1,033,000               1,564,000
       Mortgage notes payable........................................            19,719,000              29,975,000

Business combination:
       Real estate facilities........................................                     -             (48,000,000)
       Other assets..................................................                     -                (452,000)
       Accrued and other liabilities.................................                     -               1,218,000
       Common stock..................................................                     -                  23,000
       Paid-in capital...............................................                     -              46,787,000


Conversion of operating partnership units into shares of
common stock:........................................................
       Minority interest - common units..............................                     -             (33,023,000)
       Common stock..................................................                     -                  18,000
       Paid-in capital...............................................                     -              33,005,000

Adjustment to reflect minority interest to underlying ownership
interest:............................................................
       Minority interest - common units..............................             1,252,000              12,736,000
       Paid-in capital...............................................            (1,252,000)            (12,736,000)

Adjustment to acquisition cost (see Note 2):
       Real estate facilities........................................                     -              (1,315,000)
       Intangible assets.............................................                     -               1,315,000

Capitalization of developed projects:
       Real estate facilities........................................            12,146,000                       -
       Construction in progress......................................           (12,146,000)                      -




                             See accompanying notes.
                                       6



                             PS BUSINESS PARKS, INC.
              NOTES TO CONDENSED CONSOLIDATED FINANCIAL STATEMENTS
                               September 30, 1999
                                   (Unaudited)



1.   Organization and description of business

     Organization

     PS Business Parks, Inc. ("PSB" or the "Company"), a California corporation,
     is the successor to American Office Park  Properties,  Inc.  ("AOPP") which
     merged with and into Public Storage Properties XI, Inc. ("PSP 11") on March
     17,  1998  (the  "Merger").  The name of the  Company  was  changed  to "PS
     Business  Parks,  Inc." in  connection  with the  Merger.  See Note 3 for a
     description of the Merger and its terms.

     Based upon the terms of the Merger, the transaction for financial reporting
     and  accounting  purposes has been  accounted for as a reverse  acquisition
     whereby  AOPP is  deemed  to have  acquired  PSP11.  However,  PSP11 is the
     continuing  legal entity and  registrant  for both  Securities and Exchange
     Commission  filing  purposes  and  income  tax  reporting   purposes.   All
     subsequent  references to PSB or the Company for periods prior to March 17,
     1998 shall refer to AOPP.

     Description of business

     PSB  is a  fully-integrated,  self-managed  real  estate  investment  trust
     ("REIT") that acquires,  owns, operates and develops commercial  properties
     containing  commercial and industrial rental space. PSB is the sole general
     partner of PS Business Parks,  L.P. (the "Operating  Partnership")  through
     which the Company conducts most of its activities.  From 1986 through 1996,
     PSB's sole  business  activity  consisted of the  management  of commercial
     properties  owned primarily by Public Storage,  Inc. ("PSI") and affiliated
     entities.

     Commencing in 1997, PSB began to own and operate commercial  properties for
     its own behalf.  At September 30, 1999,  PSB and the Operating  Partnership
     collectively  owned and operated 123 commercial  properties  (approximately
     12.0 million net rentable  square feet) located in 11 states.  In addition,
     the Operating Partnership managed 37 commercial  properties  (approximately
     1.0  million  net  rentable  square  feet) on behalf of PSI and  affiliated
     entities.

2.   Summary of significant accounting policies

     Basis of presentation

     The accompanying unaudited condensed consolidated financial statements have
     been prepared in accordance with generally accepted  accounting  principles
     for interim  financial  information and with  instructions to Form 10-Q and
     Article 10 of Regulation S-X.  Accordingly,  they do not include all of the
     information  and  footnotes  required  by  generally  accepted   accounting
     principles  for  complete  financial  statements.  The  preparation  of the
     condensed  consolidated  financial  statements in conformity with generally
     accepted  accounting  principles  requires management to make estimates and
     assumptions that affect the amounts reported in the condensed  consolidated
     financial  statements and accompanying  notes.  Actual results could differ
     from estimates.  In the opinion of management,  all adjustments (consisting
     of normal recurring  accruals)  necessary for a fair presentation have been
     included.  Operating  results for the three and nine months ended September
     30, 1999 are not necessarily indicative of the results that may be expected
     for the year ended December 31, 1999. For further information, refer to the
     consolidated  financial  statements and footnotes thereto included in PSB's
     annual report on Form 10-K for the year ended December 31, 1998.

     The condensed consolidated financial statements include the accounts of PSB
     and  the  Operating   Partnership.   At  September  30,  1999,   PSB  owned
     approximately 72.5% of the common units of the Operating Partnership.  PSB,
     as the  sole  general  partner  of the  Operating  Partnership,  has  full,
     exclusive  and  complete  responsibility  and  discretion  in managing  and
     controlling the Operating  Partnership.  Historical financial data of PSP11
     have not been included in the historical financial statements of PSB.

                                       7


     Cash and cash equivalents

     PSB considers all highly liquid  investments  with an original  maturity of
     three  months or less at the date of purchase to be cash  equivalents.  The
     carrying amount of cash and cash equivalents approximates fair value.

     Real estate facilities

     Costs  related  to  the   improvements   of  properties  are   capitalized.
     Expenditures  for  repairs  and  maintenance  are  charged to expense  when
     incurred.  Buildings  and equipment are  depreciated  on the  straight-line
     method over the estimated useful lives, which are generally 30 and 5 years,
     respectively.

     Interest cost  incurred  during the period of  construction  of real estate
     facilities is capitalized.  Construction in progress  includes $852,000 and
     $268,000 of  capitalized  interest costs at September 30, 1999 and December
     31, 1998,  respectively.  The Company capitalized  $584,000 during the nine
     months ended  September  30, 1999. No interest was  capitalized  during the
     nine months ended September 30, 1998.

     Intangible assets

     Intangible assets consist of property  management  contracts for properties
     managed,  but not owned, by PSB. The intangible  assets are being amortized
     over seven years. As properties managed have been subsequently  acquired by
     PSB, the unamortized  basis of intangible assets related to such properties
     is included in the cost of  acquisition of such  properties.  In connection
     with the Merger,  PSB  acquired 13  properties  and included in the cost of
     such properties is $1,315,000 (which was net of accumulated amortization of
     $194,000) of costs previously  classified as intangible assets.  Intangible
     assets are net of  accumulated  amortization  of $799,000  and  $573,000 at
     September 30, 1999 and December 31, 1998, respectively.

     Evaluation of asset impairment

     PSB evaluates its assets used in operations,  by identifying  indicators of
     impairment  and by comparing the sum of the estimated  undiscounted  future
     cash flows for each asset to the asset's carrying  amount.  When indicators
     of impairment are present and the sum of the undiscounted future cash flows
     is less  than the  carrying  value of such  asset,  an  impairment  loss is
     recorded equal to the difference between the asset's current carrying value
     and its value based on  discounting  its  estimated  future cash flows.  At
     September 30, 1999, no such indicators of impairment have been identified.

     Borrowings from an affiliate

     The Company  borrowed  $41.4 million from PSI during the nine months ending
     September  30, 1999.  The notes bore  interest at 5.5% (per annum) and were
     repaid as of April 30, 1999.

     Revenue and expense recognition

     All leases are classified as operating leases.  Rental income is recognized
     on a straight-line basis over the terms of the leases.  Reimbursements from
     tenants for real estate taxes and other recoverable  operating expenses are
     recognized as revenue in the period the applicable costs are incurred.

     Costs incurred in connection with leasing  (primarily  tenant  improvements
     and leasing  commissions)  are  capitalized  and  amortized  over the lease
     period.

     Property management fees are recognized in the period earned.

                                       8


     General and administrative expense

     General and administrative expense includes executive compensation,  office
     expense,  professional  fees,  state  income  taxes,  cost  of  acquisition
     personnel and other such administrative items. Such amounts include amounts
     incurred by PSI on behalf of PSB, which were subsequently charged to PSB in
     accordance with the allocation  methodology pursuant to the cost allocation
     and administrative service agreement between PSB and PSI.

     Acquisition and development costs

     Internal acquisition and development costs are expensed as incurred.

     Income taxes

     During  1997,  PSB  qualified  and intends to continue to qualify as a real
     estate investment trust ("REIT"), as defined in Section 856 of the Internal
     Revenue  Code. As a REIT,  PSB is not subject to federal  income tax to the
     extent  that it  distributes  at least  95% of its  taxable  income  to its
     shareholders.  In addition, REITs are subject to a number of organizational
     and  operating  requirements.  If the Company fails to qualify as a REIT in
     any  taxable  year,  the  Company  will be subject  to  federal  income tax
     (including  any  applicable  alternative  minimum tax) based on its taxable
     income using corporate income tax rates.  Even if the Company qualifies for
     taxation as a REIT,  the Company may be subject to certain  state and local
     taxes on its income and property and to federal  income and excise taxes on
     its  undistributed   taxable  income.  The  Company  believes  it  met  all
     organizational  and  operating  requirements  to  maintain  its REIT status
     during 1998 and intends to  continue  to meet such  requirements  for 1999.
     Accordingly,   no  provision   for  income  taxes  has  been  made  in  the
     accompanying financial statements.

     Net income per common share

     Per share  amounts are computed  using the weighted  average  common shares
     outstanding.  "Diluted" weighted average common shares outstanding  include
     the  dilutive  effect of stock  options  under the treasury  stock  method.
     "Basic"  weighted average common shares  outstanding  excludes such effect.
     Earnings per common share has been calculated as follows:





                                                                 For the Three Months Ended      For the Nine Months Ended
                                                                        September 30,                  September 30,
                                                               -----------------------------   ------------------------------
                                                                    1999            1998            1999           1998
                                                               ------------    -------------   --------------  --------------
                                                                                                   

Net income allocable to common shareholders                    $  9,383,000    $   9,748,000   $   28,218,000  $   21,124,000
                                                               ============    =============   ==============  ==============

Weighted average common shares outstanding:
  Basic weighted average common shares outstanding..........     23,641,000       23,636,000       23,639,000      17,920,000

  Net effect of dilutive  stock  options - based
    on treasury stock method using average market price.....         83,000           60,000           74,000          70,000
                                                               ------------    -------------   --------------  --------------
  Diluted weighted average common shares outstanding........     23,724,000       23,696,000       23,713,000      17,990,000
                                                               ============    =============   ==============  ==============


Basic earnings per common share.............................   $       0.40    $        0.41   $         1.19  $         1.18
                                                               ============    =============   ==============  ==============
Diluted earnings per common share...........................   $       0.40    $        0.41   $         1.19  $         1.17
                                                               ============    =============   ==============  ==============



                                       9


     Comprehensive Income

     Effective   January  1,  1998,   PSB  adopted  SFAS  No.  130,   "Reporting
     Comprehensive Income." SFAS No. 130 requires a separate statement to report
     the  components  of  comprehensive  income for each  period  reported.  The
     adoption  of SFAS  No.  130  did not  have an  impact  on  PSB's  reporting
     presentation.

     Segment Reporting

     Effective  January 1, 1998,  PSB adopted SFAS No. 131,  "Disclosures  about
     Segments  of  an  Enterprise  and  Related   Information."   SFAS  No.  131
     established  standards  for  the way  public  business  enterprises  report
     information  about operating  segments in annual  financial  statements and
     requires that those enterprises report selected information about operating
     segments in interim financial reports.  SFAS 131 also establishes standards
     for related disclosures about products and services,  geographic areas, and
     major  customers.  As management views the Company as operating in a single
     segment as described in Note 1, the adoption of SFAS No. 131 did not affect
     PSB's disclosure of segment information.

     Reclassifications

     Certain  reclassifications  have been made to the financial  statements for
     1998 in order to conform to the 1999 presentation.

3.   Business combination

     On March 17, 1998,  AOPP merged into PSP11,  a publicly  traded real estate
     investment  trust and an affiliate of PSI. Upon  consummation of the Merger
     of AOPP into PSP11,  the  surviving  corporation  was renamed "PS  Business
     Parks, Inc." (PSB as defined in Note 1). In connection with the Merger:

      *   Each  outstanding  share of PSP11  common  stock,  which did not elect
          cash,  continued  to be owned by current  holders.  A total of 106,155
          PSP11 common shares elected to receive cash of $20.50 per share.

      *   Each  share of PSP11  common  stock  Series B and each  share of PSP11
          common  stock  Series C converted  into 0.8641  shares of PSP11 common
          stock.

      *   Each share of AOPP common  stock  converted  into 1.18 shares of PSP11
          common stock.

      *   Concurrent with the Merger, PSP11 exchanged 11 mini-warehouses and two
          properties  that combine  mini-warehouse  and commercial  space for 11
          commercial  properties  owned by PSI.  The fair value of each group of
          real estate facilities was approximately $48 million.

     The  Merger  has been  accounted  for as a reverse  merger  whereby  PSB is
     treated as the acquirer using the purchase method. This has been determined
     based upon the following:  (i) the former  shareholders  and unitholders of
     PSB owned in excess of 80% of the merged  companies  and (ii) the  business
     focus  post-Merger  will  continue to be that of PSB's which  includes  the
     acquisition,  ownership and management of commercial  properties.  Prior to
     the Merger,  PSP11's business focus had been primarily on the ownership and
     operation of its self-storage  facilities which  represented  approximately
     81% of its portfolio.

                                       10


     Allocations of the total  acquisition  cost to the net assets acquired were
     made based upon the fair value of PSP11's assets and  liabilities as of the
     date of the Merger.  The acquisition cost and the fair market values of the
     assets  acquired and  liabilities  assumed in the Merger are  summarized as
     follows:

          Acquisition cost:

          Issuance of common stock.........       $46,810,000
          Cash.............................           424,000
                                                  ------------
          Total acquisition cost...........       $47,234,000
                                                  ============

          Allocation of acquisition cost:

          Real estate facilities...........       $48,000,000
          Other assets.....................           452,000
          Accrued and other liabilities....       (1,218,000)
                                                  ------------
          Total allocation.................       $47,234,000
                                                  ============

     The historical operating results of PSP11 prior to the Merger have not been
     included in PSB's historical operating results. Pro forma data for the nine
     months ended  September 30, 1998 as though the Merger and related  exchange
     of  properties  have been  effective at the  beginning of fiscal 1998 is as
     follows:

                                                  Nine months ended
                                                 September 30, 1998
                                                 ------------------

     Revenues..............................         $64,853,000
     Net income............................         $21,908,000
     Net income per share - basic..........         $      1.18
     Net income per share - diluted........         $      1.18

     The pro forma data does not purport to be indicative  either of the results
     of  operations  that would have  occurred  had the Merger  occurred  at the
     beginning of fiscal 1998 or of the future results of PSB.

                                       11


4.   Real estate facilities

     The activity in real estate  facilities for the nine months ended September
     30, 1999 is as follows:



                                                                                 Accumulated
                                                Land            Buildings       Depreciation            Total
                                           ---------------   ---------------    ---------------   ---------------
                                                                                      

     Balances at December 31, 1998......   $   176,241,000   $   536,697,000    $   (22,517,000)  $   690,421,000
     Property acquisitions..............        13,770,000        66,537,000                  -        80,307,000
     Developed projects.................         2,341,000         9,805,000                  -        12,146,000
     Capital improvements...............                 -        10,546,000                  -        10,546,000
     Depreciation expense...............                 -                 -        (21,415,000)      (21,415,000)
                                           ---------------   ---------------    ---------------   ---------------
     Balances at September 30, 1999.....   $   192,352,000   $   623,585,000    $   (43,932,000)  $   772,005,000
                                           ===============   ===============    ===============   ===============



5.   Leasing activity

     The Company  leases space in its real estate  facilities  to tenants  under
     non-cancelable  leases  generally  ranging  from one to ten  years.  Future
     minimum rental revenues  excluding recovery of expenses as of September 30,
     1999 under these leases are as follows:

         1999 (October - December)...........         $   25,623,000
         2000................................             88,247,000
         2001................................             63,685,000
         2002................................             42,843,000
         2003................................             28,028,000
         Thereafter..........................             51,406,000
                                                      --------------
                                                      $  299,832,000
                                                      ==============

     In addition to minimum  rental  payments,  tenants pay  reimbursements  for
     their pro rata  share of  specified  operating  expenses,  which  amount to
     $12,369,000 and $7,051,000 for the nine months ended September 30, 1999 and
     1998, respectively. These amounts are included as rental income and cost of
     operations in the accompanying condensed consolidated statements of income.

6.   Revolving line of credit

     The Company  extended its unsecured line of credit (the "Credit  Facility")
     with Wells Fargo Bank.  The Credit  Facility has a borrowing  limit of $100
     million and a revised  expiration  date of August 6, 2002.  The  expiration
     date  may be  extended  by one  year  on  each  anniversary  of the  Credit
     Facility.  Interest on outstanding  borrowings is payable  monthly.  At the
     option of the  Company,  the rate of  interest  charged is equal to (i) the
     prime rate or (ii) a rate  ranging from the London  Interbank  Offered Rate
     ("LIBOR") plus 0.75% to LIBOR plus 1.35% depending on the Company's  credit
     ratings and coverage ratios,  as defined  (currently LIBOR plus 1.00%).  In
     addition, the Company is required to pay an annual commitment fee of 0.25%.

     Under  covenants  of the Credit  Facility,  the  Company is required to (i)
     maintain a balance sheet  leverage  ratio (as defined) of less than 0.50 to
     1.00, (ii) maintain  interest and fixed charge coverage ratios (as defined)
     of not less than 2.25 to 1.0 and 1.75 to 1.0, respectively,  (iii) maintain
     a  minimum  total   shareholders'   equity  (as  defined)  and  (iv)  limit
     distributions to 95% of funds from operations.  In addition, the Company is
     limited  in its  ability to incur  additional  borrowings  (the  Company is
     required to maintain unencumbered assets with an aggregate book value equal
     to or greater than two times the Company's unsecured recourse debt) or sell
     assets.  The Company was in  compliance  with the  covenants  of the Credit
     Facility at September 30, 1999.

                                       12


7.   Mortgage notes payable




         Mortgage notes at September 30, 1999 consist of the following:

                                                                                   

             7.125% mortgage note, secured by one commercial property, principal
                  and interest payable monthly, due May 2006......................       8,794,000
             8.4% mortgage note, secured by six commercial properties, principal
                  and interest payable monthly, due November 1999.................       8,554,000
             8.19% mortgage note, secured by one commercial property, principal
                  and interest payable monthly, due March 2007....................       6,710,000
             8.125% mortgage note, secured by one commercial property, principal
                  and interest payable monthly, due February 2009.................       6,396,000
             8.125% mortgage note, secured by one commercial property, principal
                  and interest payable monthly, due July 2005.....................       5,352,000
             7.28% mortgage note, secured by two commercial properties, principal
                  and interest payable monthly, due February 2003.................       4,332,000
             8% mortgage note, secured by one commercial  property, principal and
                  interest payable monthly, due April 2003........................       2,128,000
             8.5% mortgage note, secured by one commercial property, principal
                  and interest payable monthly, due July 2007.....................       1,910,000
             8% mortgage note, secured by one commercial property, principal and
                  interest payable monthly, due April 2003........................       1,652,000
                                                                                       -----------
                                                                                       $45,828,000
                                                                                       ===========


     At September 30, 1999, approximate principal maturities of mortgage notes
payable are as follows:

            1999 (October - December)...........           $    8,762,000
            2000................................                  872,000
            2001................................                  942,000
            2002................................                1,018,000
            2003................................                8,004,000
            Thereafter..........................               26,230,000
                                                           --------------
                                                           $   45,828,000
                                                           ==============
                                       13


8.   Minority interest - common units

     The Company presents the accounts of PSB and the Operating Partnership on a
     consolidated basis. Ownership interest in the Operating Partnership,  other
     than PSB's interest,  are classified as minority  interest in the condensed
     consolidated financial statements.  Minority interest in income consists of
     the  minority  interests'  share of the  condensed  consolidated  operating
     results.

     Beginning  one year from the date of  admission  as a limited  partner  and
     subject to certain limitations  described below, each limited partner other
     than  PSB has the  right  to  require  the  redemption  of its  partnership
     interest.

     A limited  partner that  exercises its  redemption  right will receive cash
     from the Operating  Partnership  in an amount equal to the market value (as
     defined  in  the  Operating  Partnership   Agreement)  of  the  partnership
     interests  redeemed.  In lieu of the  Operating  Partnership  redeeming the
     partner  for  cash,  PSB,  as  general  partner,  has the right to elect to
     acquire the partnership interest directly from a limited partner exercising
     its redemption right, in exchange for cash in the amount specified above or
     by  issuance  of one share of PSB  common  stock  for each unit of  limited
     partnership interest redeemed.

     A limited  partner  cannot  exercise  its  redemption  right if delivery of
     shares  of PSB  common  stock  would be  prohibited  under  the  applicable
     articles of incorporation,  if the general partner believes that there is a
     risk  that  delivery  of shares of common  stock  would  cause the  general
     partner to no longer  qualify as a REIT,  would  cause a  violation  of the
     applicable securities laws, or would result in the Operating Partnership no
     longer being treated as a partnership for federal income tax purposes.

     At September 30, 1999,  there were 7,443,356 common units owned by minority
     interests  (7,305,355 were owned by PSI and affiliated entities and 138,001
     were owned by  unaffiliated  third parties).  On a fully  converted  basis,
     assuming all 7,443,356  minority  interest common units were converted into
     shares of common stock of PSB at September 30, 1999, the minority interests
     would own approximately 23.9% of the common shares outstanding.  At the end
     of each reporting  period,  PSB determines the amount of equity (book value
     of net assets) which is allocable to the minority  interest  based upon the
     ownership interest and an adjustment is made to the minority interest, with
     a  corresponding  adjustment  to paid-in  capital,  to reflect the minority
     interests' equity in the Company.

9.   Minority interest - preferred units

     On April 23, 1999, the Operating  Partnership completed a private placement
     of 510,000  preferred units with a preferred  distribution  rate of 8 7/8%.
     The net proceeds from the placement of preferred  units were  approximately
     $12.5 million and were used to repay borrowings from an affiliate.

     On  September  3,  1999,  the  Operating  Partnership  completed  a private
     placement of 3,200,000  preferred units with a preferred  distribution rate
     of 8 3/4%.  The net proceeds  from the  placement  of preferred  units were
     approximately $78 million and part of the proceeds will be used to prepay a
     mortgage note payable of approximately $8.5 million.

     On September 7 and 23, 1999, the Operating  Partnership  completed  private
     placements of 1,200,000 and 400,000 preferred units,  respectively,  with a
     preferred  distribution rate of 8 7/8%. The net proceeds from the placement
     of preferred units were approximately $39.2 million.

     The Operating Partnership has the right to redeem the preferred units on or
     after the fifth  anniversary  of the issuance date at the original  capital
     contribution plus the cumulative  priority return to the redemption date to
     the extent not previously distributed. The preferred units are exchangeable
     for Cumulative  Redeemable  Preferred Stock of the respective  series of PS
     Business  Parks,  Inc.  on or after  the tenth  anniversary  of the date of
     issuance  at the option of the  Operating  Partnership  or  majority of the
     holders of the  preferred  units.  The  Preferred  Stock will have the same
     distribution  rate and par  value as the  respective  units  and will  have
     equivalent terms to those described in Note 11.

                                       14


10.  Property management contracts

     The Operating Partnership manages industrial,  office and retail facilities
     for PSI and entities affiliated with PSI. These facilities,  all located in
     the United  States,  operate  under the "Public  Storage"  or "PS  Business
     Parks" name.

     The property management  contracts provide for compensation of five percent
     of the gross revenue of the facilities  managed.  Under the  supervision of
     the property owners, the Operating Partnership coordinates rental policies,
     rent  collections,  marketing  activities,  the purchase of  equipment  and
     supplies,  maintenance  activities,  and the  selection  and  engagement of
     vendors, suppliers and independent contractors.  In addition, the Operating
     Partnership  assists  and  advises  the  property  owners  in  establishing
     policies for the hire,  discharge  and  supervision  of  employees  for the
     operation  of  these  facilities,  including  property  managers,  leasing,
     billing and maintenance personnel.

     The property management contract with PSI is for a seven year term with the
     term being  extended one year each  anniversary.  The  property  management
     contracts with  affiliates of PSI are cancelable by either party upon sixty
     days notice.

11.  Shareholders' equity

     In addition  to common and  preferred  stock,  PSB is  authorized  to issue
     100,000,000  shares of Equity Stock. The Articles of Incorporation  provide
     that the Equity Stock may be issued from time to time in one or more series
     and gives the Board of  Directors  broad  authority to fix the dividend and
     distribution rights,  conversion and voting rights,  redemption  provisions
     and liquidation rights of each series of Equity Stock.

     On April 30, 1999, PSB issued 2,200,000 depositary shares each representing
     1/1,000  of a share of 9 1/4%  Cumulative  Preferred  Stock,  Series A. Net
     proceeds  from  the  public   perpetual   preferred   stock  offering  were
     approximately  $53.1  million  and were  used to repay  borrowings  from an
     affiliate and a mortgage  note payable of  approximately  $11 million.  The
     remaining proceeds were used for investment in real estate.

     Holders of the  Company's  preferred  stock will not be entitled to vote on
     most matters, except under certain conditions. In the event of a cumulative
     arrearage  equal to six quarterly  dividends,  the holders of the preferred
     stock will have the right to elect two  additional  members to serve on the
     Company's  Board of Directors  until all events of default have been cured.
     At September 30, 1999, there were no dividends in arrears.

     Except under certain conditions relating to the Company's  qualification as
     a REIT, the preferred  stock is not redeemable  prior to April 30, 2004. On
     or after April 30, 2004,  the preferred  stock will be  redeemable,  at the
     option of the Company,  in whole or in part, at $25 per  depositary  share,
     plus any accrued and unpaid dividends.

     The Company paid  distributions  to its common and  preferred  shareholders
     totaling $17,729,000 ($0.75 per common share) and $2,134,000 ($0.969965 per
     depositary  share),  respectively,  for the nine months ended September 30,
     1999.

                                       15


12.  Recent accounting pronouncements

     In June 1998, the Financial Accounting Standards Board issued SFAS No. 133,
     "Accounting for Derivative  Instruments and Hedging  Activities,"  which is
     required to be adopted in years beginning  after June 15, 2000.  Management
     anticipates  that the  adoption  of SFAS No.  133 will  have no  effect  on
     earnings  or  the  financial  position  of PSB  since  no  derivatives  are
     currently being used.

13.  Commitments and contingencies

     PSB is subject to the risks  inherent in the  ownership  and  operation  of
     commercial  real estate.  These include,  among others,  the risks normally
     associated with changes in the general economic climate, trends in the real
     estate industry,  creditworthiness of tenants, competition,  changes in tax
     laws,  interest rate levels,  the  availability  of financing and potential
     liability under environmental and other laws.

     Substantially  all of  the  properties  have  been  subjected  to  Phase  I
     environmental  reviews.  Such reviews have not revealed,  nor is management
     aware of, any  probable or  reasonably  possible  environmental  costs that
     management  believes  would  be  material  to  the  condensed  consolidated
     financial statements except as discussed below.

     The Company acquired a property in Beaverton,  Oregon ("Creekside Corporate
     Park") in May 1998.  A property  adjacent to  Creekside  Corporate  Park is
     currently     the     subject     of     an     environmental      remedial
     investigation/feasibility  study that is being conducted by the current and
     past  owners of the  property,  pursuant  to an order  issued by the Oregon
     Department of Environmental  Quality ("ODEQ").  As part of that study, ODEQ
     ordered the property owners to sample soil and groundwater on the Company's
     property to determine the nature and extent of contamination resulting from
     past  industrial  operations  at the  property  subject to the  study.  The
     Company,  which is not a party of the Order on Consent,  executed  separate
     Access  Agreements with the property owners to allow access to its property
     to conduct the required  sampling and testing.  The sampling and testing is
     ongoing,   and  preliminary   results  from  one  area  indicate  that  the
     contamination from the property subject to the study may have migrated onto
     a portion of Creekside Corporate Park owned by the Company.

     There  is no  evidence  that  any  past  or  current  use of the  Creekside
     Corporate Park property contributed in any way to the contamination that is
     the subject of the current investigation.  Nevertheless, upon completion of
     the study, it is likely that removal or remedial  measures will be required
     to address any  contamination  detected  during the current  investigation,
     including  any  contamination  on or under  the  Creekside  Corporate  Park
     property.  Because  of the  preliminary  nature of the  investigation,  the
     Company  cannot  predict  the  outcome  of the  investigation,  nor  can it
     estimate the costs of any  remediation  or removal  activities  that may be
     required.

     The Company believes that it bears no  responsibility  or liability for the
     contamination.  In the event the Company is ultimately  deemed  responsible
     for any costs relating to this matter,  the Company believes that the party
     from whom the property was purchased will be  responsible  for any expenses
     or   liabilities   that  the   Company  may  incur  as  a  result  of  this
     contamination.

     PSB currently is neither  subject to any other material  litigation nor, to
     management's  knowledge,  is any material litigation  currently  threatened
     against PSB other than routine  litigation and  administrative  proceedings
     arising in the ordinary  course of  business.  Based on  consultation  with
     counsel,  management  believes  that  these  items will not have a material
     adverse impact on the Company's condensed  consolidated  financial position
     or results of operations.

                                       16



Item 2:  Management's Discussion and Analysis of Financial Condition and
         Results of Operations
         ---------------------------------------------------------------

          General:   Private  Securities   Litigation  Reform  Act  Safe  Harbor
Statement.  In addition to historical  information,  management's discussion and
analysis  includes  certain  forward-looking  statements  regarding  events  and
financial  trends which may affect the Company's  future  operating  results and
financial position. Such forward-looking  statements are often identified by the
words "estimate,"  "project,"  "intend," "plan," "expect," "believe," or similar
expressions.  Such statements are subject to risks and uncertainties  that could
cause the Company's actual results and financial  position to differ  materially
from that indicated by the forward-looking  statement. Such factors include, but
are not limited to a change in economic conditions in the various markets served
by the Company's operations which would adversely affect the level of demand for
rental of commercial  space and the cost  structure of the Company.  Readers are
cautioned not to place undue reliance on these forward-looking statements, which
speak only as of the date  hereof.  The  Company  undertakes  no  obligation  to
publicly release the result of any revisions to these forward-looking statements
to reflect  events or  circumstances  after the date  hereof or to  reflect  the
occurrence of unanticipated events.

          Overview:   Comparisons  between  the  three  and  nine  months  ended
September  30, 1999 and 1998 will  reflect  significant  levels of  acquisitions
during 1998 and the first nine months of 1999.

          During  1998,  the  Company  added  4.9  million  square  feet  to its
portfolio.  The cost of these acquisitions was approximately  $378 million.  The
acquisitions  added  square  footage  to each  of the  Company's  existing  core
markets.  The Company  acquired  1,687,000  square feet in Texas at an aggregate
cost of approximately $102 million; 1,001,000 square feet in Portland, Oregon at
an aggregate cost of  approximately  $115 million;  1,442,000 square feet in the
Northern  Virginia/Maryland  market at an aggregate cost of  approximately  $108
million;  422,000  square feet in Southern  California  at an aggregate  cost of
approximately  $25 million and 307,000 square feet in Northern  California at an
aggregate cost of approximately $25 million.  In addition,  the Company acquired
62,000  square  feet in the  Merger at an  aggregate  cost of  approximately  $3
million in a market the Company does not consider a core market.

          During the nine months ended  September  30, 1999,  the Company  added
922,000  square  feet to its  portfolio.  The  cost of  these  acquisitions  was
approximately $80 million.  These acquisitions  increased the Company's presence
in existing markets,  which the Company believes have characteristics  necessary
for long-term  growth.  The Company  acquired 306,000 square feet in Texas at an
aggregate cost of approximately $23 million, 405,000 square feet in the Northern
Virginia/Maryland  market at an aggregate cost of approximately  $40 million and
211,000 square feet in Northern California for approximately $17 million.

          Results of Operations: Net income for the three months ended September
30, 1999 was $10,655,000 compared to $9,748,000 for the same period in 1998. Net
income  allocable  to common  shareholders  (net  income  less  preferred  stock
dividends) for the three months ended September 30, 1999 was $9,383,000 compared
to  $9,748,000  for the same  period in 1998.  Net income per common  share on a
diluted basis was $0.40 (based on weighted average diluted shares outstanding of
23,724,000) for the three months ended September 30, 1999 compared to net income
per common share on a diluted basis of $0.41 (based on weighted  average diluted
shares  outstanding of  23,696,000)  for the same period in 1998. Net income for
the nine months ended September 30, 1999 was $30,352,000 compared to $21,124,000
for the same period in 1998. Net income  allocable to common  shareholders  (net
income less preferred  stock  dividends) for the nine months ended September 30,
1999 was  $28,218,000  compared to $21,124,000  for the same period in 1998. Net
income per common share on a diluted basis was $1.19 (based on weighted  average
diluted shares  outstanding of 23,713,000)  for the nine months ended  September
30,  1999  compared to net income per common  share on a diluted  basis of $1.17
(based on weighted  average  diluted shares  outstanding of 17,990,000)  for the
same period in 1998.  The  increases in net income  reflects  PSB's  significant
growth in its asset base through the  acquisition  of commercial  properties and
increase in net operating income from the consistent group of properties.

                                       17


          The Company's  property  operations  account for almost all of the net
operating  income  earned by the  Company.  The  following  table  presents  the
pre-depreciation  operating  results  of the  properties  for the three and nine
months ended September 30, 1999 and 1998:




                                                              Three Months Ended September 30,
                                                              ----------------------------------
                                                                    1999               1998               Change
                                                              --------------      --------------       ----------
                                                                                              

Rental income:
     Facilities owned throughout each period (50
       facilities, 6.4 million net rentable square feet)..      $16,353,000         $15,208,000             7.5%
     Facilities acquired subsequent to January 1998 (73
       facilities, 5.5 million net rentable square feet)..       16,215,000          10,427,000            55.5%
                                                              --------------      --------------       ----------
Total rental income.......................................      $32,568,000         $25,635,000            27.0%
                                                              ==============      ==============       ==========

Cost of operations (excluding depreciation):
     Facilities owned throughout each period..............       $4,671,000          $4,773,000            (2.1%)
     Facilities acquired subsequent to January 1998.......        4,249,000           2,606,000            63.0%
                                                              --------------      --------------       ----------
Total cost of operations..................................       $8,920,000           7,379,000            20.9%
                                                              ==============      ==============       ==========

Net operating income (rental income less cost of operations):
     Facilities owned throughout each period..............      $11,682,000         $10,435,000            12.0%
     Facilities acquired subsequent to January 1998.......       11,966,000           7,821,000            53.0%
                                                              --------------      --------------       ----------
Total net operating income................................      $23,648,000         $18,256,000            29.5%
                                                              ==============      ==============       ==========





                                                               Nine Months Ended September 30,
                                                              ---------------------------------
                                                                   1999               1998              Change
                                                              -------------      --------------       ----------
                                                                                              

Rental income:
     Facilities owned throughout each period (50
       facilities, 6.4 million net rentable square feet)..    $  47,231,000      $   43,152,000             9.5%
     Facilities  acquired  subsequent  to January 1998 (73
       facilities, 5.5 million net rentable square feet)..       45,313,000          18,307,000           147.5%
                                                              -------------      --------------       ----------
Total rental income.......................................    $  92,544,000      $   61,459,000            50.6%
                                                              =============      ==============       ==========

Cost of operations (excluding depreciation):
     Facilities owned throughout each period..............    $  13,998,000      $   13,830,000             1.2%
     Facilities acquired subsequent to January 1998.......       11,953,000           4,531,000           163.8%
                                                              -------------      --------------       ----------
Total cost of operations..................................    $  25,951,000          18,361,000            41.3%
                                                              =============      ==============       ==========

Net operating income (rental income less cost of operations):
     Facilities owned throughout each period..............    $  33,233,000      $   29,322,000            13.3%
     Facilities acquired subsequent to January 1998.......       33,360,000          13,776,000           142.2%
                                                              -------------      --------------       ----------
Total net operating income................................    $  66,593,000      $   43,098,000            54.5%
                                                              =============      ==============       ==========


                                       18


     Rental  income and rental  income less cost of  operations or net operating
income ("NOI") prior to  depreciation  are summarized for the three months ended
September 30, 1999 by major geographic region below:




                                   Square       Percent         Rental         Percent                        Percent
          Region                   Footage      of Total        Income         of Total          NOI          of Total
- ---------------------------      -----------   ----------      ------------    --------     ------------      --------
                                                                                            

Southern California.......        3,091,000        25.8%        $8,761,000        26.9%      $6,494,000          27.5%
Northern California.......        1,317,000        11.0%         3,398,000        10.4%       2,582,000          10.9%
Virginia..................        1,612,000        13.4%         5,254,000        16.1%       3,771,000          15.9%
Maryland..................        1,104,000         9.2%         3,469,000        10.7%       2,568,000          10.9%
Texas.....................        2,857,000        23.8%         6,497,000        19.9%       4,367,000          18.5%
Oregon....................        1,172,000         9.8%         3,700,000        11.4%       2,899,000          12.3%
Other.....................          833,000         7.0%         1,489,000         4.6%         967,000           4.0%
                                 -----------   ----------      ------------    --------     ------------      --------
                                 11,986,000       100.0%       $32,568,000       100.0%     $23,648,000         100.0%
                                 ===========   ==========      ============    ========     ============      ========


         Rental income and rental income less cost of operations or net
operating income ("NOI") prior to depreciation are summarized for the nine
months ended September 30, 1999 by major geographic region below:



                                   Square       Percent         Rental         Percent                        Percent
          Region                   Footage      of Total        Income         of Total          NOI          of Total
- ---------------------------      -----------   ---------       -----------     --------     -----------      ---------
                                                                                            

Southern California.......        3,091,000        25.8%       $25,163,000        27.2%     $18,638,000          28.0%
Northern California.......        1,317,000        11.0%         8,830,000         9.5%       6,643,000          10.0%
Virginia..................        1,612,000        13.4%        13,497,000        14.6%       9,609,000          14.4%
Maryland..................        1,104,000         9.2%        10,215,000        11.0%       7,328,000          11.0%
Texas.....................        2,857,000        23.8%        19,444,000        21.0%      12,919,000          19.4%
Oregon....................        1,172,000         9.8%        11,036,000        11.9%       8,690,000          13.0%
Other.....................          833,000         7.0%         4,359,000         4.8%       2,766,000           4.2%
                                 ----------    ---------       -----------     --------     -----------      ---------
                                 11,986,000       100.0%       $92,544,000       100.0%     $66,593,000         100.0%
                                 ==========    =========       ===========     ========     ===========      =========


          Supplemental  Property  Data and  Trends:  In order  to  evaluate  the
performance  of  the  Company's  overall  portfolio,   management  analyzes  the
operating  performance of a consistent  group of 62 properties  (7.2 million net
rentable square feet). These 62 properties in which the Company currently has an
ownership  interest (herein referred to as the "Same Park" facilities) have been
managed by the Company since January 1998.  The following  table  summarizes the
pre-depreciation  historical  operating  results of the "Same  Park"  facilities
excluding the effects of accounting for rental income on a straight-line  basis.
The "Same Park" facilities now represent approximately 60% of the square footage
of the Company's portfolio at September 30, 1999.

                                       19


                     "Same Park" Facilities (62 Properties)
                     --------------------------------------



                                                                                Three months ended September 30,
                                                                       ------------------------------------------------
                                                                           1999               1998              Change
                                                                       -------------      -------------         -------
                                                                                                       

     Rental income (1)............................................     $  18,697,000      $  17,216,000            8.6%
     Cost of operations...........................................         5,896,000          5,869,000            0.5%
                                                                       -------------      -------------         -------
          Net operating income....................................     $  12,801,000      $  11,347,000           12.8%
                                                                       =============      =============         =======
     Gross margin (2).............................................             68.5%              65.9%            2.6%

     Weighted average for period:
     ---------------------------

          Occupancy...............................................            96.7%              95.3%            1.4%

          Annualized realized rent per sq. ft.(3).................     $      10.74             $10.03             7.1%






                                                                                 Nine months ended September 30,
                                                                       ------------------------------------------------
                                                                           1999             1998 (4)            Change
                                                                       -------------      -------------         -------
                                                                                                       

     Rental income (1)............................................     $  54,025,000      $  49,824,000            8.4%
     Cost of operations...........................................        16,944,000         16,583,000            2.2%
                                                                       -------------      -------------         -------
          Net operating income....................................     $  37,081,000      $  33,241,000           11.6%
                                                                       =============      =============         =======
     Gross margin (2).............................................             68.6%              66.7%            1.9%

     Weighted average for period:
     ---------------------------

          Occupancy...............................................             96.7%              94.4%            2.3%

          Annualized realized rent per sq. ft.(3).................      $     10.34       $       9.77             5.8%


- ------------------
(1)  Rental income does not include the effect of straight-line accounting.
(2)  Gross margin is computed by dividing property net operating income by
     rental income.
(3)  Realized rent per square foot represents the actual revenues earned per
     occupied square foot.
(4)  Operations for the nine months ended September 30, 1998 represent the
     historical operations of the 62 properties; however, the Company did not
     own all of the properties throughout the periods presented and therefore
     such operations are not reflected in the Company's historical operating
     results. All such properties were owned effective March 17, 1998.

                                       20


     The following tables summarize the "Same Park" operating results by major
geographic region for the three months ended September 30, 1999 and 1998:



                                Revenues          Revenues       Percent           NOI               NOI         Percent
                                  1999              1998         Increase          1999             1998         Increase
                              -------------     -------------   ---------      -------------    -------------   ---------
                                                                                              

Southern California.......      $8,449,000        $7,439,000      13.6%          $6,061,000       $5,180,000       17.0%
Northern California.......       2,101,000         1,945,000       8.0%           1,544,000        1,374,000       12.4%
Texas.....................       1,829,000         1,714,000       6.7%             943,000          868,000        8.6%
Virginia..................       2,360,000         2,204,000       7.1%           1,608,000        1,443,000       11.4%
Maryland..................       2,291,000         2,318,000      (1.2%)          1,611,000        1,529,000        5.4%
Arizona...................         732,000           693,000       5.6%             465,000          386,000       20.5%
Other.....................         935,000           903,000       3.5%             569,000          567,000        0.4%
                              -------------     -------------   ---------      -------------    -------------   ---------
                               $18,697,000       $17,216,000       8.6%         $12,801,000      $11,347,000       12.8%
                              =============     =============   =========      =============    =============   =========


          The following  tables  summarize the "Same Park" operating  results by
major geographic region for the nine months ended September 30, 1999 and 1998:




                                Revenues          Revenues        Percent          NOI               NOI          Percent
                                  1999              1998         Increase          1999             1998         Increase
                              -------------     -------------   ---------      -------------    -------------   ---------
                                                                                              

Southern California.......     $24,023,000       $21,451,000      12.0%         $17,382,000      $14,884,000       16.8%
Northern California.......       6,139,000         5,711,000       7.5%           4,511,000        4,034,000       11.8%
Texas.....................       5,451,000         4,982,000       9.4%           2,939,000        2,579,000       14.0%
Virginia..................       6,789,000         6,447,000       5.3%           4,525,000        4,218,000        7.3%
Maryland..................       6,795,000         6,504,000       4.5%           4,719,000        4,559,000        3.5%
Arizona...................       2,097,000         2,029,000       3.4%           1,311,000        1,255,000        4.5%
Other.....................       2,731,000         2,700,000       1.1%           1,694,000        1,712,000       (1.1%)
                              -------------     -------------   ---------      -------------    -------------   ---------
                               $54,025,000       $49,824,000       8.4%         $37,081,000      $33,241,000       11.6%
                              =============     =============   =========      =============    =============   =========


          The growth in the strong Southern California market was accentuated by
increasing  occupancies  in the New York Common  portfolio  acquired in December
1997.  The  performance of the Texas  facilities  reflects  improvements  in the
Austin and San  Antonio  facilities  as well as  economies  of scale  created by
substantial  square  footage  added to the  Texas  market  over the last  twelve
months.

          Facility  Management  Operations:  The Company's  facility  management
accounts for a small portion of the Company's net operating  income.  During the
three  months ended  September  30, 1999,  $97,000 in net  operating  income was
recognized from facility management  operations compared to $97,000 for the same
period in 1998. During the nine months ended September 30, 1999, $281,000 in net
operating income was recognized from facility management  operations compared to
$391,000 for the same period in 1998.  Facility  management  fees have decreased
due to the Company's acquisition of properties previously managed.

          Interest and Other Income: Interest and other income primarily reflect
earnings on cash balances. Interest and other income were $592,000 for the three
months  ended  September  30, 1999  compared to $533,000  for the same period in
1998.  Interest  and  other  income  were  $885,000  for the nine  months  ended
September 30, 1999 compared to $1,077,000  for the same period in 1998.  Average
cash balances for the three months ended  September 30, 1999 were  approximately
$47 million  compared to $41 million for the same period in 1998.  Average  cash
balances for the nine months ended  September  30, 1999 were  approximately  $24
million compared to $28 million for the same period in 1998.

                                       21


          Cost of  Operations:  Cost of  operations  for the three  months ended
September 30, 1999 was $8,920,000  compared to $7,379,000 for the same period in
1998.  Cost of  operations  for the nine  months  ended  September  30, 1999 was
$25,951,000  compared  to  $18,361,000  for the same  period  in  1998.  Cost of
operations for the three months ended  September 30, 1999 consists  primarily of
property  taxes  ($2,889,000),  property  maintenance  ($1,171,000),   utilities
($1,403,000)  and direct payroll  ($1,065,000).  Cost of operations for the nine
months  ended   September  30,  1999  consists   primarily  of  property   taxes
($8,163,000),  property  maintenance  ($3,761,000),  utilities  ($3,805,000) and
direct  payroll  ($3,242,000).  The increases are due primarily to the growth in
the total  square  footage of the  Company's  portfolio of  properties.  Cost of
operations as a percentage of rental  income  decreased  from 28.8% to 27.4% and
from  29.9% to 28.0% for the three and nine  months  ended  September  30,  1999
compared to the same period in 1998,  respectively,  as a result of economies of
scale  achieved  through the  acquisition  of  properties  in  existing  markets
partially offset by an increase in property tax expense.

          Depreciation and Amortization  Expense:  Depreciation and amortization
expense for the three months ended September 30, 1999 were  $7,594,000  compared
to $4,865,000 for the same period in 1998. Depreciation and amortization expense
for the nine  months  ended  September  30,  1999 were  $21,641,000  compared to
$11,421,000  for the same period in 1998. The increase is due to the acquisition
of real estate facilities in 1998 and 1999.

          General and Administrative Expense: General and administrative expense
was $742,000 for the three months ended  September 30, 1999 compared to $593,000
for the same period in 1998. General and  administrative  expense was $2,339,000
for the nine months ended September 30, 1999 compared to $1,589,000 for the same
period  in 1998.  The  increase  is due to the  increased  size and  acquisition
activities  of the  Company.  Included in general and  administrative  costs are
acquisition costs and abandoned transaction costs.  Acquisition expenses for the
three  months ended  September  30, 1999 and 1998 were  $139,000  and  $279,000,
respectively.  Abandoned  transaction  costs were none and $11,000 for the three
months ended September 30, 1999 and 1998, respectively. Acquisition expenses for
the nine months ended  September  30, 1999 and 1998 were  $324,000 and $557,000,
respectively.  Abandoned transaction costs were $30,000 and $15,000 for the nine
months ended September 30, 1999 and 1998, respectively.

     Interest Expense:  Interest expense was $977,000 for the three months ended
September  30,  1999  compared  to  $667,000  for the same  period in 1998.  The
increase  is  attributable  to mortgage  notes  assumed in  connection  with the
acquisition of real estate facilities ($785,000 in interest expense) and line of
credit  costs  ($366,000)  net of $174,000 of interest  expense  capitalized  to
ongoing  construction  projects for the three months ended  September  30, 1999.
Interest  expense was  $2,658,000  for the nine months ended  September 30, 1999
compared to $1,736,000 for the same period in 1998. The increase is attributable
to mortgage  notes assumed in  connection  with the  acquisition  of real estate
facilities  ($2,285,000 in interest  expense) and line of credit costs and other
short tern borrowings ($957,000) net of $584,000 of interest expense capitalized
to ongoing construction projects for the nine months ended September 30, 1999.

          Minority Interest in Income:  Minority interest in income reflects the
income allocable to equity interests in the Operating  Partnership which are not
owned by the  Company.  Minority  interest in income for the three  months ended
September 30, 1999 was $4,369,000 ($1,022,000 allocated to preferred unitholders
and $3,347,000 allocated to common unitholders) compared to $3,013,000 allocated
to common  unitholders for the same period in 1998.  Minority interest in income
for the  nine  months  ended  September  30,  1999 was  $10,769,000  ($1,236,000
allocated  to  preferred   unitholders   and  $9,533,000   allocated  to  common
unitholders) compared to $8,696,000 allocated to common unitholders for the same
period in 1998.  The increase in minority  interest in income is due to improved
operating  results,  the issuance of additional  common units in connection with
the acquisition of real estate facilities and the private placement of preferred
units.

Liquidity and Capital Resources
- -------------------------------

          Net cash  provided by operating  activities  for the nine months ended
September  30,  1999 and 1998 was  $62,745,000  and  $41,842,000,  respectively.
Management believes that the Company's internally generated net cash provided by
operating  activities  will  continue to be  sufficient to enable it to meet its
operating expenses, capital improvements, debt service requirements and maintain
the current level of distribution to shareholders.

          The following table  summarizes the Company's  ability to make capital
improvements  to maintain  its  facilities  through the use of cash  provided by
operating activities. The remaining cash flow is available to the Company to pay
distributions to shareholders and to acquire property interests.

                                       22




                                                                         Nine months ended September 30,
                                                                              1999              1998
                                                                        ----------------  ---------------
                                                                                    


Net income..........................................................     $   30,352,000    $  21,124,000
Depreciation and amortization.......................................         21,641,000       11,421,000
Minority interest in income.........................................         10,769,000        8,696,000
Change in working capital...........................................            (17,000)         601,000
                                                                        ----------------  ---------------
Net cash provided by operating activities...........................         62,745,000       41,842,000


Maintenance capital expenditures....................................         (2,153,000)      (2,117,000)
Tenant improvements.................................................         (3,857,000)      (2,588,000)
Capitalized lease commissions.......................................         (1,479,000)      (1,325,000)
                                                                        ----------------  ---------------
Funds available for distributions to shareholders, minority
  interests, acquisitions and other corporate purposes..............         55,256,000       35,812,000

Cash distributions to shareholders and minority interests...........        (26,667,000)     (22,145,000)
                                                                        ----------------  ---------------

Excess funds available for acquisitions and other corporate purposes     $   28,589,000    $  13,667,000
                                                                        ================  ===============


          The Company's  capital  structure is  characterized  by a low level of
leverage.  As of September  30, 1999,  the Company had nine fixed rate  mortgage
notes  payable  totaling   $45,828,000   which   represented  5%  of  its  total
capitalization (based on book value, including minority interests and debt). The
weighted average interest rate for the mortgage notes is 7.92%.

     The Company  extended its unsecured line of credit (the "Credit  Facility")
with Wells Fargo Bank. The Credit Facility has a borrowing limit of $100 million
and a revised  expiration  date of August 6, 2002.  The  expiration  date may be
extended by one year on each  anniversary of the Credit  Agreement.  Interest on
outstanding  borrowings is payable  monthly.  At the option of the Company,  the
rate of interest  charged is equal to (i) the prime rate or (ii) a rate  ranging
from the London Interbank  Offered Rate ("LIBOR") plus 0.75% to LIBOR plus 1.35%
depending on the  Company's  credit  ratings and interest  coverage  ratios,  as
defined  (currently LIBOR plus 1.00%).  In addition,  the Company is required to
pay an annual commitment fee of 0.25%.

          The  Company  expects to fund its  growth  strategies  with  permanent
capital,  including  issuances  of common  and  preferred  stock and  internally
generated  retained  cash  flows.  The Company  may  finance  acquisitions  on a
temporary basis with borrowings from its line of credit.  The Company intends to
repay amounts  borrowed under the credit facility from  undistributed  cash flow
or, as market conditions  permit and as determined to be advantageous,  from the
public or private  placement of preferred and common stock or formation of joint
ventures.  The  Company  targets  a  leverage  ratio  of 40%  and a  Funds  from
Operations ("FFO") to combined fixed charges and preferred  distributions  ratio
of 3.0 to 1.0. As of September 30, 1999 and for the nine months then ended,  the
leverage  ratio was 22% and the FFO to  combined  fixed  charges  and  preferred
distributions coverage ratio was 9.5 to 1.0.

          In April 1999, the Company  completed a private placement of preferred
OP units and a public  offering of  depositary  shares  representing  fractional
interests in perpetual  preferred stock resulting in net proceeds totaling $65.6
million.  The net proceeds from the  placement of preferred OP units,  completed
April 23, 1999 were approximately  $12.5 million and the preferred OP units have
a preferred distribution rate of 8 7/8% on a stated value of $12.75 million. The
preferred OP units have equivalent terms to those of perpetual  preferred stock.
Net proceeds from the public perpetual  preferred stock offering completed April
30, 1999 were $53.1  million,  and the preferred  stock has a dividend rate of 9
1/4% on a stated value of $55 million.  Proceeds from the issuances were used to
pay off borrowings  from an affiliate and a portion was used to repay a mortgage
note payable of approximately $11 million. The remaining proceeds have been used
for investment in real estate.

          On September 3, 1999,  the Operating  Partnership  completed a private
placement of 3,200,000  preferred units with a preferred  distribution rate of 8
3/4%. The net proceeds from the placement of preferred units were  approximately
$78  million  and part of the  proceeds  will be used to prepay a mortgage  note
payable of approximately $8.5 million.

                                       23


          On  September 7 and 23,  1999,  the  Operating  Partnership  completed
private placements of 1,200,000 and 400,000 preferred units, respectively,  with
a preferred  distribution rate of 8 7/8%. The net proceeds from the placement of
preferred units were approximately $39.2 million.

          Funds  from  Operations:  FFO is defined as net  income,  computed  in
accordance  with  generally  accepted  accounting  principles  ("GAAP"),  before
depreciation,  amortization,  minority  interest in income,  straight  line rent
adjustments and  extraordinary or non-recurring  items. FFO is presented because
the Company considers FFO to be a useful measure of the operating performance of
a REIT which,  together with net income and cash flows provide  investors with a
basis to evaluate the operating and cash flow  performances  of a REIT. FFO does
not represent net income or cash flows from  operations as defined by GAAP.  FFO
does  not take  into  consideration  scheduled  principal  payments  on debt and
capital improvements.  Accordingly, FFO is not necessarily a substitute for cash
flow or net income as a measure of liquidity or operating performance or ability
to make acquisitions and capital improvements or ability to pay distributions or
debt principal payments.  Also, FFO as computed and disclosed by the Company may
not be comparable to FFO computed and disclosed by other REITs.

         FFO for the Company is computed as follows:



                                                                         Nine months ended September 30,
                                                                              1999              1998
                                                                        ----------------  ---------------
                                                                                    

Net income allocable to common shareholders........................       $  28,218,000     $  21,124,000
  Depreciation and amortization....................................          21,641,000        11,421,000
  Minority interest in income - common units.......................           9,533,000         8,696,000
  Less effects of straight-line rents..............................          (2,544,000)         (924,000)
                                                                        ----------------  ---------------
Consolidated FFO allocable to common shareholders and common
unitholders........................................................          56,848,000        40,317,000

FFO allocated to minority interest - common units..................         (13,179,000)      (11,757,000)
                                                                        ----------------  ---------------

FFO allocated to common shareholders...............................      $   43,669,000    $   28,560,000
                                                                        ================  ===============


     Capital Expenditures:  During the nine months ended September 30, 1999, the
Company  incurred a total of $7.5 million in maintenance  capital  expenditures,
tenant improvements and capitalized lease commissions.  In addition, the Company
made $2.6 million of renovation  expenditures.  On a recurring annual basis, the
Company expects $0.90 to $1.20 per square foot in recurring  maintenance capital
expenditures,  tenant improvements and capitalized lease commissions. During the
remainder  of 1999,  the  Company  expects  to make an  additional  $400,000  in
additional expenditures to continue renovation on two properties in Texas.

          Distributions:  The  Company  has  elected and intends to qualify as a
REIT for federal income tax purposes.  As a REIT,  the Company must meet,  among
other tests,  sources of income,  share  ownership and certain  asset tests.  In
addition,  the Company is not taxed on that portion of its taxable  income which
is  distributed  to its  shareholders  provided that at least 95% of its taxable
income is so distributed to its shareholders prior to filing of its tax return.

          The Board of  Directors  declared a  quarterly  dividend  of $0.25 per
common  share on November 9, 1999.  The Board of  Directors  has  established  a
distribution  policy to maximize the retention of cash flow and only  distribute
the minimum  amount  required  for the  Company to maintain  its tax status as a
REIT.  In  addition,  the Board of  Directors  declared a quarterly  dividend of
$0.578125 per share on the 2,200,000 depositary shares each representing 1/1,000
of a share of 9 1/4% Cumulative  Preferred Stock,  Series A.  Distributions  are
payable  on  December  31,  1999 to  shareholders  of  record as of the close of
business on December 15, 1999.

                                       24


Impact of Year 2000
- -------------------

          The Company  utilizes PSI's  information  systems in connection with a
cost sharing and  administrative  services  agreement.  The Company and PSI have
completed  an  assessment  of all  of its  hardware  and  software  applications
including  those  affecting  the Company to identify  susceptibility  to what is
commonly  referred to as the "Y2K issue" whereby certain computer  programs have
been using two digits rather than four to define the  applicable  year.  Certain
computer   programs  or  hardware   with  the  Y2K  issue  have   date-sensitive
applications  or embedded chips that may recognize a date using "00" as the year
1900 rather than the year 2000,  resulting in  miscalculations or system failure
causing disruptions to operations.

          The Company in conjunction with PSI has two phases in its process with
respect to each of its  systems;  i)  assessment,  whereby  the  Company and PSI
evaluate  whether the system is Y2K  compliant  and  identify the plan of action
with respect to remediating  any Y2K issues  identified and ii)  implementation,
whereby  the  Company  and PSI  complete  the  plan of  action  prepared  in the
assessment phase and verify that Y2K compliance has been achieved.

          Implementations  have been completed for PSI's  critical  applications
that impact the Company,  including its general ledger and related systems, that
are believed to have Y2K issues.  Contingency  plans have been developed for use
in  case  the  assessment  did not  identify  all  such  Y2K  issues,  or if the
implementation  were  subsequently  determined to not fully remediate Y2K issues
that were identified.  The Company presently believes that the impact of the Y2K
issue on its system can be  mitigated.  However,  if the plan for  ensuring  Y2K
compliance and the related  contingency plans were to fail, be insufficient,  or
not be  implemented  on a  timely  basis,  operations  of the  Company  could be
materially impacted.

          Certain of the Company's other  non-computer  related systems that may
be impacted by the Y2K issue,  such as security  systems,  have been  evaluated.
Based upon its  evaluation,  the Company  has no reason to believe  that lack of
compliance  or  failure  of  required  solutions  would  materially  impact  its
operations.

          The Company exchanges  electronic data with certain outside vendors in
the banking and payroll  processing areas. The Company has been advised by these
vendors that their  systems are Y2K  compliant.  The Company is not aware of any
other vendors,  suppliers,  or other external agents with a Y2K issue that would
materially  impact the Company's  results of operations,  liquidity,  or capital
resources.  However,  the Company has no means of ensuring that external  agents
will be Y2K  compliant,  and  there can be no  assurance  that the  Company  has
identified  all such  external  agents.  The  inability  of  external  agents to
complete  their Y2K  compliance  process in a timely  fashion  could  materially
impact the  Company.  The effect of  non-compliance  by  external  agents is not
determinable.

          The total cost of PSI's Y2K  compliance  activities  (which  primarily
consists of the costs of  implementing  new  systems)  will be  allocated to all
entities  that use the PSI computer  systems.  The amount to be allocated to the
Company is estimated at approximately $250,000.

          The costs of the  projects  and the date on which PSI and the  Company
expect to achieve Y2K compliance are based upon management's best estimates, and
were derived utilizing  numerous  assumptions of future events.  There can be no
assurance that these estimates will be achieved, and actual results could differ
materially  from those  anticipated.  There can be no assurance that PSI and the
Company have identified all potential Y2K issues either within the Company or at
external  agents.  In  addition,  the  impact of the Y2K  issue on  governmental
entities and utility providers and the resultant impact on the Company,  as well
as disruptions in the general economy,  may be material but cannot be reasonably
determined or quantified.

                                       25


Item 3.  Quantitative and Qualitative Disclosures about Market Risk
         ----------------------------------------------------------

          To  limit  the  Company's   exposure  to  market  risk,   the  Company
principally  finances its operations  and growth with  permanent  equity capital
consisting  of either  common or preferred  stock.  At September  30, 1999,  the
Company's  debt as a percentage of  shareholders'  equity (based on book values)
was 8.3%.

          The Company's market risk sensitive instruments include mortgage notes
payable which totaled  $45,828,000 at September 30, 1999.  Substantially  all of
the Company's mortgage notes payable bear interest at fixed rates. See Note 7 of
the Notes to Condensed Consolidated  Financial Statements for terms,  valuations
and  approximate  principal  maturities  of the  mortgage  notes  payable  as of
September 30, 1999. Based on borrowing rates currently available to the Company,
the carrying amount of debt approximates fair value.

                                       26


PART II. OTHER INFORMATION

Item 1.  Legal Proceedings
         -----------------

        PS Business Parks, L.P. v. Principal Mutual Life Insurance Company, et
        ----------------------------------------------------------------------
al., Circuit Court of Washington County, Oregon (filed April 29, 1999)
- ---

          In May 1998, the Company acquired a property in Beaverton,  Oregon. An
adjacent property is the subject of an environmental remedial investigation. For
additional information on the investigation,  please refer to the Company's 1998
annual report on Form 10-K under "Item 7.  Management's  Discussion and Analysis
of Financial  Condition  and Results of Operations - Risk Factors - Our Business
Could Be Subject to Environmental Liabilities."

          In April 1999, the Company  commenced an action against the sellers of
the property  seeking  indemnification  for any damages and expenses that may be
incurred by the Company in this matter and for other relief.  The Company is not
currently able to quantify the extent of such damages and expenses.

Item 6.  Exhibits and Reports on Form 8-K
         --------------------------------

         (a)   Exhibits

2.1      Amended and Restated Agreement and Plan of Reorganization among
         Registrant, American Office Park Properties, Inc. ("AOPP") and Public
         Storage, Inc. ("PSI") dated as of December 17, 1997. Filed with
         Registrant's Registration Statement No. 333-45405 and incorporated
         herein by reference.

3.1      Restated Articles of Incorporation. Filed with Registrant's
         Registration Statement No. 333-78627 and incorporated herein by
         reference.

3.2      Certificate of Determination of Preferences of 8 3/4% Series C
         Cumulative Redeemable Preferred Stock of PS Business Parks, Inc. Filed
         herewith.

3.3      Certificate of Determination of Preferences of 8 7/8% Series X
         Cumulative Redeemable Preferred Stock of PS Business Parks, Inc. Filed
         herewith.

3.4      Amendment to Certificate of Determination of Preferences of 8 7/8%
         Series X Cumulative Redeemable Preferred Stock of PS Business Parks,
         Inc. Filed herewith.

3.5      Restated Bylaws. Filed with Registrant's Current Report on Form 8-K
         dated March 17, 1998 and incorporated herein by reference.

10.1     Amended Management Agreement between Storage Equities, Inc. and Public
         Storage Commercial Properties Group, Inc. dated as of February 21,
         1995. Filed with PSI's Annual Report on Form 10-K for the year ended
         December 31, 1994 and incorporated herein by reference.

10.2     Registrant's 1997 Stock Option and Incentive Plan. Filed with
         Registrant's Registration Statement No. 333-48313 and incorporated
         herein by reference.

10.3     Agreement of Limited Partnership of PS Business Parks, L.P. Filed with
         Registrant's Quarterly Report on Form 10-Q for the quarterly period
         ended June 30, 1998 and incorporated herein by reference.

10.4     Merger and Contribution Agreement dated as of December 23, 1997 among
         Acquiport Two Corporation, Acquiport Three Corporation, New York State
         Common Retirement Fund, American Office Park Properties, L.P., AOPP and
         AOPP Acquisition Corp. Three. Filed with Registrant's Registration
         Statement No. 333-45405 and incorporated herein by reference.

                                       27


10.5     Agreement Among Shareholders and Company dated as of December 23, 1997
         among Acquiport Two Corporation, AOPP, American Office Park Properties,
         L.P. and PSI. Filed with Registrant's Registration Statement No.
         333-45405 and incorporated herein by reference.

10.6     Amendment to Agreement Among Shareholders and Company dated as of
         January 21, 1998 among Acquiport Two Corporation, AOPP, American Office
         Park Properties, L.P. and PSI. Filed with Registrant's Registration
         Statement No. 333-45405 and incorporated herein by reference.

10.7     Non-Competition Agreement dated as of December 23, 1997 among PSI,
         AOPP, American Office Park Properties, L.P. and Acquiport Two
         Corporation. Filed with Registrant's Registration Statement No.
         333-45405 and incorporated herein by reference.

10.8     Employment Agreement between AOPP and Ronald L. Havner, Jr. dated as of
         December 23, 1997. Filed with Registrant's Registration Statement No.
         333-45405 and incorporated herein by reference.

10.9     Employment Agreement between AOPP and Mary Jayne Howard dated as of
         December 23, 1997. Filed with Registrant's Registration Statement No.
         333-45405 and incorporated herein by reference.

10.10    Employment Agreement between Registrant and J. Michael Lynch dated as
         of May 20, 1998. Filed with Registrant's Quarterly Report on Form 10-Q
         for the quarterly period ended June 30, 1998 and incorporated herein by
         reference.

10.11    Common Stock Purchase Agreement dated as of January 23, 1998 among AOPP
         and the Investors signatory thereto. Filed with Registrant's
         Registration Statement No. 333-45405 and incorporated herein by
         reference.

10.12    Registration Rights Agreement dated as of January 30, 1998 among AOPP
         and the Investors signatory thereto. Filed with Registrant's
         Registration Statement No. 333-45405 and incorporated herein by
         reference.

10.13    Registration Rights Agreement dated as of March 17, 1998 between
         Registrant and Acquiport Two Corporation ("Acquiport Registration
         Rights Agreement"). Filed with Registrant's Quarterly Report on Form
         10-Q for the quarterly period ended June 30, 1998 and incorporated
         herein by reference.

10.14    Letter dated May 20, 1998 relating to Acquiport Registration Rights
         Agreement. Filed with Registrant's Quarterly Report on Form 10-Q for
         the quarterly period ended June 30, 1998 and incorporated herein by
         reference.

10.15    Revolving Credit Agreement dated August 6, 1998 among PS Business
         Parks, L.P., Wells Fargo Bank, National Association, as Agent, and the
         Lenders named therein. Filed with Registrant's Quarterly Report on Form
         10-Q for the quarterly period ended June 30, 1998 and incorporated
         herein by reference.

10.16    First Amendment to Revolving Credit Agreement dated as of August 19,
         1999 among PS Business Parks, L.P., Wells Fargo Bank, National
         Association, as Agent, and the Lenders named therein. Filed herewith.

10.17    Form of Indemnity Agreement. Filed with Registrant's Quarterly Report
         on Form 10-Q for the quarterly period ended March 31, 1998 and
         incorporated herein by reference.

10.18    Cost Sharing and Administrative Services Agreement dated as of November
         16, 1995 by and among PSCC, Inc. and the owners listed therein. Filed
         with Registrant's Quarterly Report on Form 10-Q for the quarterly
         period ended March 31, 1998 and incorporated herein by reference.

10.19    Amendment to Cost Sharing and Administrative Services Agreement dated
         as of January 2, 1997 by and among PSCC, Inc. and the owners listed
         therein. Filed with Registrant's Quarterly Report on Form 10-Q for the
         quarterly period ended March 31, 1998 and incorporated herein by
         reference.

                                       28


10.20    Accounts Payable and Payroll Disbursement Services Agreement dated as
         of January 2, 1997 by and between PSCC, Inc. and American Office Park
         Properties, L.P. Filed with Registrant's Quarterly Report on Form 10-Q
         for the quarterly period ended March 31, 1998 and incorporated herein
         by reference.

10.21    Amendment to Agreement of Limited Partnership of PS Business Parks,
         L.P. Relating to 8 7/8% Series B Cumulative Redeemable Preferred Units,
         dated as of April 23, 1999. Filed with Registrant's Quarterly Report on
         Form 10-Q for the quarterly period ended March 31, 1999 and
         incorporated herein by reference.

10.22    Amendment to Agreement of Limited Partnership of PS Business Parks,
         L.P. Relating to 9 1/4% Series A Cumulative Redeemable Preferred Units,
         dated as of April 30, 1999. Filed with Registrant's Quarterly Report on
         Form 10-Q for the quarterly period ended March 31, 1999 and
         incorporated herein by reference.

10.23    Amendment to Agreement of Limited Partnership of PS Business Parks,
         L.P. Relating to 83/4% Series C Cumulative Redeemable Preferred Units,
         dated as of September 3, 1999. Filed herewith.

10.24    Amendment to Agreement of Limited Partnership of PS Business Parks,
         L.P. Relating to 8 7/8% Series X Cumulative Redeemable Preferred Units,
         dated as of September 7, 1999. Filed herewith.

10.25    Amendment to Agreement of Limited Partnership of PS Business Parks,
         L.P. Relating to Additional 8 7/8% Series X Cumulative Redeemable
         Preferred Units, dated as of September 23, 1999. Filed herewith.

11       Statement re: Computation of Earnings per Share. Filed herewith.

12       Statement re: Computation of Ratio of Earnings to Fixed Charges. Filed
         herewith.

27       Financial Data Schedule. Filed herewith.

         (b)   Reports on Form 8-K

               None.

                                       29


                                   SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

                                           Dated:  November 10, 1999

                                           PS BUSINESS PARKS, INC.

                                           By: /s/ Jack Corrigan
                                               -------------------------
                                               Jack Corrigan
                                               Vice President and
                                               Chief Financial Officer

                                       30