EXHIBIT 10.1


                    FOURTH AMENDMENT TO AMENDED AND RESTATED
                       AGREEMENT OF LIMITED PARTNERSHIP OF
                        PSA INSTITUTIONAL PARTNERS, L.P.,
                        A CALIFORNIA LIMITED PARTNERSHIP


                       (CREATING SERIES J PREFERRED UNITS)

         This Fourth  Amendment  (the  "AMENDMENT")  to the Amended and Restated
Agreement  of  Limited  Partnership  of  PSA  Institutional  Partners,  L.P.,  a
California  Limited  Partnership,  dated  March 29,  2000 as  amended by (i) the
Amendment  to Amended  and  Restated  Agreement  of Limited  Partnership  of PSA
Institutional  Partners,  L.P.,  dated as of August  11,  2000,  (ii) the Second
Amendment  to Amended  and  Restated  Agreement  of Limited  Partnership  of PSA
Institutional  Partners,  L.P.,  dated as of August 11, 2000 and (iii) the Third
Amendment  to Amended  and  Restated  Agreement  of Limited  Partnership  of PSA
Institutional  Partners,  L.P.,  dated as of October 12, 2004 (the  "PARTNERSHIP
AGREEMENT")  is made and entered into as of May 9, 2006 (the  "EFFECTIVE  DATE")
with  reference  to the  following  facts:

         A. Pursuant to Section 3.3 of the  Partnership  Agreement,  the General
Partner is authorized to cause the Partnership to issue certain additional units
of limited partnership interest without the consent of the Limited Partners.

         B. The General  Partner has determined that it is in the best interests
of the  Partnership  to  create a new  class of  units,  with the  designations,
preferences and other rights, powers and duties set forth in this Amendment,  to
be known as Series J  Preferred  Units,  and to issue  those  units as set forth
below.  Although the  proceeds  from the issuance of those units may be used for
any Partnership  purpose,  the General Partner currently  anticipates having the
Partnership  use those  proceeds to acquire  through  another entity an indirect
interest in the assets of Shurgard  Storage  Centers,  Inc.

         C. Unless otherwise defined in this Amendment,  capitalized terms shall
have the meanings given to them in the Partnership Agreement.

         The parties agree as follows:

         1. The  following  definitions  shall be inserted into Section 1 of the
Partnership Agreement in the appropriate alphabetical order:

         "BEL LIMITED PARTNERS" means Belair, Belcrest, Belmar, Belport, Belrose
         Realty   Corporation    ("BELROSE"),    Belshire   Realty   Corporation
         ("BELSHIRE"), Belterra Realty Corporation ("BELTERRA"), Belwater Realty
         Corporation  ("BELWATER"),  Clearwood Realty Corporation  ("CLEARWOOD")
         and Montebello.



         "SERIES J PREFERRED  UNITS" means the series of  partnership  interests
         designated  as the  "7.25%  Series J  Cumulative  Redeemable  Perpetual
         Preferred  Units"  entitled to the rights  described in this Agreement.
         The Series J Preferred Units are Exchangeable  Preferred Units, and the
         Corresponding  Preferred Stock with respect to those units is the 7.25%
         Cumulative Preferred Stock, Series J, of the Company."

         2. The definition of "PRIORITY RETURN" in the Partnership  Agreement is
amended by inserting the following at the end of clause (i):

         ", and for the Series J  Preferred  Units an amount  equal to seven and
         one quarter  percent  (7.25%) per annum of the stated  value of $25 per
         unit"

In  addition,  notwithstanding  anything  to the  contrary  in  the  Partnership
Agreement, to reflect the issuance of certain Series J Preferred Units as of the
Effective  Date,  the Priority  Return  relating to the quarter in 2006 in which
those  Series J  Preferred  Units are issued  shall be  53/90th of the  Priority
Return that would accrue for a full calendar quarter.

         3. The  definition  of  "PARITY  PREFERRED  UNITS"  in the  Partnership
Agreement  shall be amended by inserting the phrase "Series J Preferred  Units,"
into the second sentence thereof before the phrase "Series N Preferred Units".

         4. On the Effective Date, in accordance with that certain  Contribution
Agreement,  dated as of May 9,  2006,  by and among  Belair,  Belport,  Belrose,
Belshire,  Belterra, Belwater and Clearwood (collectively,  the "CONTRIBUTORS"),
the Partnership and the General Partner,  the Contributors  shall make a capital
contribution   to  the   Partnership  in  the  amount  of  One  Hundred  Million
($100,000,000)  Dollars and the  Partnership  shall  issue to the  Contributors,
collectively,  Four Million  (4,000,000)  Series J Preferred  Units. In order to
reflect  the  issuance  of those  Series J  Preferred  Units,  Exhibit  A to the
Partnership  Agreement is replaced  with Exhibit A in the form  attached to this
Amendment,  reflecting  that Belair holds  1,000,000  Series J Preferred  Units,
Belport holds 700,000 Series J Preferred  Units,  Belrose holds 400,000 Series J
Preferred Units, Belshire holds 500,000 Series J Preferred Units, Belterra holds
600,000  Series J Preferred  Units,  Belwater  holds 600,000  Series J Preferred
Units and Clearwood holds 200,000 Series J Preferred Units."

         5. Section 6.6.1 of the Partnership Agreement is amended to read in its
entirety as follows:

         "6.6.1. RIGHT OF OPTIONAL REDEMPTION.  The Series J, Series N, Series O
         and Series P  Preferred  Units may not be  redeemed  prior to the fifth
         (5th)  anniversary of the issuance date of the particular  series to be
         redeemed.  The Series NN Preferred  Units may not be redeemed  prior to
         March 17, 2010. The Series Z Preferred  Units may not be redeemed prior
         to March 5, 2009.  On or after the fifth  anniversary  of the  issuance
         date of each of the Series J, Series N, Series O and Series P Preferred
         Units,  and on or after  March 17,  2010 with  respect to the Series NN
         Preferred  Units,  and on or after  March 5, 2009 with  respect  to the

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         Series Z  Preferred  Units,  the  Partnership  shall  have the right to
         redeem the Series J,  Series N, Series O, Series P, Series NN or Series
         Z Preferred  Units,  respectively,  in whole or in part, at any time or
         from time to time,  upon not less than  thirty (30) nor more than sixty
         (60) days'  written  notice,  at a redemption  price,  payable in cash,
         equal to the  Liquidation  Preference per Series J, Series N, Series O,
         Series P,  Series NN or Series Z  Preferred  Unit to be  redeemed  (the
         "REDEMPTION  PRICE").  The  rights of  redemption  of any  subsequently
         issued  Parity  Preferred  Units shall be as  designated  in an amended
         Exhibit  A to this  Agreement.  If fewer  than  all of the  outstanding
         Parity Preferred Units of a particular  series are to be redeemed,  the
         units to be redeemed  from that series  shall be selected  pro rata (as
         nearly as practicable  without creating  fractional units)."

         6.  Section  6.7 of the  Partnership  Agreement  is  amended  to insert
"Series J" immediately before "Series N".

         7. Section 10.3 of the Partnership  Agreement is amended to read in its
entirety as follows (the effect of which is to correct  certain  misnumbering in
prior amendments and to add at the end new Section 10.3.5:

            10.3.1 SERIES O PREFERRED  UNITS.  Holders of the Series O Preferred
         Units will not have any voting rights or right to consent to any matter
         requiring  the consent or approval of the Limited  Partners,  except as
         set  forth  below.  So long as any  Series  O  Preferred  Units  remain
         outstanding, the Partnership shall not, without the affirmative vote of
         the  holders of at least a majority  of the  Series O  Preferred  Units
         outstanding  at the time,  take any of the actions  described  above in
         Sections  10.2.1,  10.2.2 and 10.2.3,  treating each reference in those
         provisions  to "Series N  Preferred  Units" as a  reference  instead to
         "Series O Preferred Units."

            10.3.2 SERIES P PREFERRED  UNITS.  Holders of the Series P Preferred
         Units will not have any voting rights or right to consent to any matter
         requiring  the consent or approval of the Limited  Partners,  except as
         set  forth  below.  So long as any  Series  P  Preferred  Units  remain
         outstanding, the Partnership shall not, without the affirmative vote of
         the  holders of at least a majority  of the  Series P  Preferred  Units
         outstanding  at the time,  take any of the actions  described  above in
         Sections  10.2.1,  10.2.2 and 10.2.3,  treating each reference in those
         provisions  to "Series N  Preferred  Units" as a  reference  instead to
         "Series P Preferred Units."

            10.3.3 SERIES NN PREFERRED UNITS. Holders of the Series NN Preferred
         Units will not have any voting rights or right to consent to any matter
         requiring  the consent or approval of the Limited  Partners,  except as
         set forth  below.  So long as any  Series  NN  Preferred  Units  remain
         outstanding, the Partnership shall not, without the affirmative vote of
         the  holders of at least a majority  of the Series NN  Preferred  Units
         outstanding  at the time,  take any of the actions  described  above in
         Sections  10.2.1,  10.2.2 and 10.2.3,  treating each reference in those
         provisions  to "Series N  Preferred  Units" as a  reference  instead to
         "Series NN Preferred Units."

            10.3.4 SERIES Z PREFERRED  UNITS.  Holders of the Series Z Preferred
         Units will not have any voting rights or right to consent to any matter
         requiring  the consent or approval of the Limited  Partners,  except as
         set  forth  below.  So long as any  Series  Z  Preferred  Units  remain
         outstanding, the Partnership shall not, without the affirmative vote of

                                       3



         the  holders of at least a majority  of the  Series Z  Preferred  Units
         outstanding  at the time,  take any of the actions  described  above in
         Sections  10.2.1,  10.2.2 and 10.2.3,  treating each reference in those
         provisions  to "Series N  Preferred  Units" as a  reference  instead to
         "Series Z Preferred Units."

            10.3.5 SERIES J PREFERRED  UNITS.  Holders of the Series J Preferred
         Units will not have any voting rights or right to consent to any matter
         requiring  the consent or approval of the Limited  Partners,  except as
         set  forth  below.  So long as any  Series  J  Preferred  Units  remain
         outstanding, the Partnership shall not, without the affirmative vote of
         the  holders of at least a majority  of the  Series J  Preferred  Units
         outstanding  at the time,  take any of the actions  described  above in
         Sections  10.2.1,  10.2.2 and 10.2.3,  treating each reference in those
         provisions  to "Series N  Preferred  Units" as a  reference  instead to
         "Series J Preferred Units."

         8.  Section  11.2 of the  Partnership  Agreement  is hereby  amended by
inserting the following  language in clause (iii) of the fourth sentence thereof
after the words "Series NN Preferred Units": "and Series J Preferred Units".

         9.  Section  12.2 of the  Partnership  Agreement  is  amended by adding
immediately after Section 12.2.4 the following Section 12.2.5:

            "12.2.5 SERIES J PREFERRED  UNITS. The Series J Preferred Units also
         shall be exchangeable in the same fashion as are the Series N Preferred
         Units:  the  provisions of Section 12.1 shall be read as if restated in
         this Section  12.2.5,  but as if each reference in those  provisions to
         "Series N  Preferred  Units"  instead  were a  reference  to  "Series J
         Preferred  Units,"  and by  treating  each  reference  to the "Series N
         Preferred  Stock"  as a  reference  to the 7.25%  Cumulative  Preferred
         Stock, Series J, of the Company.

            In addition,  notwithstanding  any provision herein to the contrary,
         so long as any Series J  Preferred  Units  remain  outstanding,  in the
         event of the occurrence of a Covered  Transaction  (defined below),  on
         the date such Covered  Transaction is completed or occurs,  the holders
         of record of the Series J Preferred  Units  (acting as a whole),  shall
         have the option to cause the  exchange of all of the Series J Preferred
         Units  outstanding  for  depositary  shares  representing  interests in
         Series J  Preferred  Stock based on the  Exchange  Ratio (as defined in
         Section  12.1.1) if the holders of a majority  of the then  outstanding
         Series J Preferred  Units elect to so exchange in  accordance  with the
         following paragraph.

            The Partnership  shall give written notice of a Covered  Transaction
         to each of the  respective  holders of record of the Series J Preferred
         Units,  at their  respective  addresses  as they appear on the transfer
         records of the Partnership, not less than thirty (30) days prior to the
         completion or occurrence  of a Covered  Transaction.  Such notice shall
         not set  forth  any  non-public  information  concerning  such  Covered

                                       4



         Transaction.  Each of the  holders of record of the Series J  Preferred
         Units  shall  have until 5:00 p.m.  (PST) on the  fifteenth  (15th) day
         following  receipt of such  notice  from the  Partnership,  to give the
         Partnership  notice of whether such holder votes in favor of having the
         Series J Preferred Units be exchanged for Series J Preferred Stock.

            Notwithstanding  any provision herein to the contrary,  with respect
         to a Covered Transaction that arises under clause (c) of the definition
         of Covered  Transaction  set forth below, in the event that the Company
         so fails to qualify as a real  estate  investment  trust for any reason
         other than an affirmative  election by the Company not to qualify,  (a)
         the  Partnership  shall  give  notice  of the  occurrence  of a Covered
         Transaction  to each of the holders of record of the Series J Preferred
         Units within 15 days after  discovery  of such failure to qualify,  (b)
         each of the  holders of record of the Series J  Preferred  Units  shall
         have  until  5:00 p.m.  (PST) on the  fifteenth  (15th)  day  following
         receipt of such notice from the  Partnership,  to give the  Partnership
         notice of such holder's vote as to whether the Series J Preferred Units
         will be exchanged  for Series J Preferred  Stock and (c) if the holders
         of not less than a majority of the then outstanding  Series J Preferred
         Units have elected to have the Series J Preferred  Units  exchanged for
         Series J Preferred  Stock, all of the Series J Preferred Units shall be
         so  exchanged  on a date not later than 45 days  following  the date of
         discovery of the Company's failure to qualify.

            For purposes of this Section 12.2.5, the term "COVERED  TRANSACTION"
         shall mean (a) the Company's  completion of a "Rule 13e-3  transaction"
         (as defined in Rule 13e-3 under the Securities Exchange Act of 1934, as
         amended  (the  "Exchange   Act"))  in  which,   as  a  result  of  such
         transaction,  the Company's common stock is no longer  registered under
         Section 12 of the Exchange  Act,  except that this clause (a) shall not
         apply to any involuntary  delisting of the Company's  common stock from
         the New York Stock  Exchange or any  national  securities  exchange (as
         defined in the Exchange Act), (b) the completion of any  transaction or
         series of  transactions  that would  result in a  Reorganization  Event
         (defined  below) of the Company or the Partnership or (c) the Company's
         failure (or election not) to qualify as a real estate  investment trust
         as defined in Section 856 (or any  successor  section) of the  Internal
         Revenue Code of 1986, as amended.

            For purposes of this Section 12.2.5, the term "REORGANIZATION EVENT"
         shall mean (x) any sale or other  disposition  of all or  substantially
         all of the assets of the  Partnership  or the Company,  as the case may
         be, to an entity that is not an affiliate  of the  Company;  or (y) any
         consolidation,   amalgamation,   merger,  business  combination,  share
         exchange,   reorganization   or  similar   transaction   involving  the
         Partnership or the Company,  as the case may be,  pursuant to which the
         Partners of the Partnership or the stockholders of the Company,  as the
         case may be,  immediately prior to the consummation of such transaction
         will own less than a  majority  of the equity  interests  in the entity

                                       5




         surviving such transaction;  provided,  however, a Reorganization Event
         shall not include any transaction contemplated by clauses (x) or (y) of
         this definition if the surviving  entity has unsecured debt outstanding
         which is rated at least the lowest credit rating level  established  as
         investment grade by at least two of Standard & Poor's, Moody's Investor
         Service and Fitch Ratings (it being  understood  that as of the date of
         this Agreement the lowest  investment grade rating of Standard & Poor's
         is BBB-, the lowest  investment grade rating of Moody's is Baa3 and the
         lowest  investment  grade  rating  of Fitch  Ratings  is BBB-) and such
         rating has been reaffirmed in light of the contemplated transaction."

         10.  Except  as  expressly  provided  in  this  Amendment,  all  of the
provisions of the Partnership Agreement are ratified and confirmed, and continue
in full force and effect.


         [THE REMAINDER OF THIS PAGE HAS BEEN INTENTIONALLY LEFT BLANK.]

                                       6



       The undersigned have signed this Amendment as of the date indicated
       above.


                            "GENERAL PARTNER:"

                            PS TEXAS HOLDINGS, LTD.,
                            a Texas limited partnership

                            By:  PS GPT Properties, Inc., a California
                                 corporation, its general partner

                                 By:      /s/ John Reyes
                                          --------------
                                          Name:  John Reyes
                                          Title: Senior Vice President and
                                                 Chief Financial Officer


                                 By:      /s/ Stephanie Heim
                                          ------------------
                                          Name:  Stephanie Heim
                                          Title: Secretary


                            "LIMITED PARTNERS:"

                            PS LPT PROPERTIES INVESTORS,
                            a Maryland business trust


                                 By:      /s/ John Reyes
                                          --------------
                                          Name: John Reyes
                                          Title:Senior Vice President and
                                                Chief Financial Officer



                                 By:      /s/ Stephanie Heim
                                         -------------------
                                         Name:  Stephanie Heim
                                         Title:    Secretary

                                       7


                       (SIGNATURES CONTINUE ON NEXT PAGE)

                            BELAIR REAL ESTATE CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President


                            BELPORT REALTY CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President


                            BELROSE REALTY CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President


                            BELSHIRE REALTY CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President

                                       8



                       (SIGNATURES CONTINUE ON NEXT PAGE)


                             BELTERRA REALTY CORPORATION,
                             a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President


                            BELWATER REALTY CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President


                            CLEARWOOD REALTY CORPORATION,
                            a Delaware corporation


                                 By:    /s/ William R. Cross
                                        --------------------
                                        Name:  William R. Cross
                                        Title: President

                                       9



                       (SIGNATURES CONTINUE ON NEXT PAGE)


                            ALL OTHER LIMITED PARTNERS

                                 By:      PS Texas Holdings, Ltd.,
                                          a Texas limited partnership,
                                          as their attorney-in-fact

                                 By:      PS GPT Properties, Inc.,
                                          a California corporation,
                                          its general partner


                                 By:      /s/ John Reyes
                                          --------------
                                          Name:  John Reyes
                                          Title: Senior Vice President and
                                                 Chief Financial Officer


                                 By:      Stephanie Heim
                                          --------------
                                          Name:  Stephanie Heim
                                          Title: Secretary


                       (SIGNATURES CONTINUE ON NEXT PAGE)

                                       10



Acknowledged and agreed, as to the
issuance of Company stock pursuant
to Section 12 of the Partnership Agreement:


"COMPANY"

PUBLIC STORAGE, INC.,
a California corporation


By:      /s/ John Reyes
         --------------
         Name:  John Reyes
         Title: Senior Vice President and
                Chief Financial Officer


By:      /s/ Stephanie Heim
         ------------------
         Name:  Stephanie Heim
         Title: Secretary

                                       11