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

                                   FORM N-CSR

                          CERTIFIED SHAREHOLDER REPORT
                                       OF
                   REGISTERED MANAGEMENT INVESTMENT COMPANIES

Investment Company Act file number: 811-4627

Name of Registrant: Vanguard Convertible Securities Fund

Address of Registrant: P.O. Box 2600
                       Valley Forge, PA 19482

Name and address of agent for service:      R. Gregory Barton, Esquire
                                            P.O. Box 876
                                            Valley Forge, PA 19482

Registrant's telephone number, including area code: (610) 669-1000

Date of fiscal year end:  November 30

Date of reporting period:  December 1, 2003 - May 31, 2004

Item 1: Reports to Shareholders

VANGUARD(R) CONVERTIBLE SECURITIES FUND

SEMIANNUAL REPORT

MAY 31, 2004

THE VANGUARD GROUP(R) LOGO



HOW TO READ YOUR FUND REPORT

This report contains information that can help you evaluate your investment.  It
includes  details  about your fund's  return and presents data and analysis that
provide insight into the fund's performance and investment approach.

By reading the letter from Vanguard's chairman,  John J. Brennan,  together with
the letter from the managers who select  securities for your fund, you'll get an
understanding  of how the fund invests and how the market  environment  affected
its  performance.   The  statistical  information  that  follows  can  help  you
understand how the fund's performance and characteristics stack up against those
of similar funds and market benchmarks.

It's  important  to keep in mind  that  the  opinions  expressed  by  Vanguard's
investment  managers  are just  that:  informed  opinions.  They  should  not be
considered  promises or advice.  The opinions,  like the  statistics,  cover the
period  through the date on the cover of this report.  As things  change--and in
the financial markets you can be certain only of change--an investment manager's
job is to evaluate  new  information  and make  adjustments,  if  necessary.  Of
course, the risks of investing in the fund are spelled out in the prospectus.

Frequent  updates on the fund's  performance and  information  about some of its
holdings are available on Vanguard.com(R).

- --------------------------------------------------------------------------------
CONTENTS

 1 letter from the chairman
 5 report from the advisor
 8 fund profile
 9 glossary of investment terms
11 performance summary
12 about your fund's expenses
14 financial statements
23 advantages of vanguard.com
- --------------------------------------------------------------------------------
SUMMARY

*    During the six months ended May 31, 2004, Vanguard  Convertible  Securities
     Fund posted a return of 3.1%,  which was somewhat lower than the returns of
     its comparative measures.
*    Financial markets across asset classes saw solid gains early in the period,
     but gave up some of those gains in the final months.
*    Convertible  securities,  which are often issued by small,  rapidly growing
     companies,   were  further  hampered  by  the  poor  performance  of  these
     companies' stocks relative to the broad market.

Want less clutter in your mailbox? Just register with VANGUARD.COM and opt to
get fund reports online.
- --------------------------------------------------------------------------------



LETTER FROM THE CHAIRMAN

Dear Shareholder,

The stock  market made  respectable  gains during the recent  fiscal  half-year,
while  bonds  barely eked out a positive  return.  As you might  expect,  hybrid
investments  posted  results midway between those of stocks and bonds during the
six months ended May 31, 2004.  Vanguard  Convertible  Securities  Fund returned
3.1%, which was lower than the results of its comparative measures.

[PICTURE OF JOHN J. BRENNAN]


- ------------------------------------------------------
TOTAL RETURNS                         SIX MONTHS ENDED
                                          MAY 31, 2004
- ------------------------------------------------------
VANGUARD CONVERTIBLE SECURITIES FUND              3.1%
CS First Boston Convertibles Index                4.6
Average Convertible Securities Fund*              4.0
Dow Jones Wilshire 5000 Index                     6.4
- ------------------------------------------------------
*Derived from data provided by Lipper Inc.


The  adjacent  table  shows  total  returns   (capital  gains  plus   reinvested
distributions)  for the fund and three  benchmarks:  the unmanaged Credit Suisse
First Boston Convertible Securities Index, the average mutual fund peer, and the
broad U.S.  stock market,  as measured by the Dow Jones  Wilshire 5000 Composite
Index.  The  fund's  starting  and ending  share  prices  and  distributions  to
shareholders  are shown on page 4. As of May 31, the fund's yield was 2.72%, 101
basis points (1.01 percentage points) lower than at the start of the period.

As you  know,  on May 14 the  Convertible  Securities  Fund  was  closed  to new
accounts and to additional purchases for existing accounts.  During the previous
12  months,  fund  assets  had more  than  doubled  as a result  of both  market
appreciation and new  investments.  Such rapid asset growth has the potential to
hamper an investment advisor's ability to put new cash to work effectively.  The
challenge  is even  greater when the target  market is a rarefied  one,  such as
convertibles,  and when the investment advisor prefers a disciplined,  bottom-up
approach to security

                                       1



selection--as does Oaktree Capital Management, your fund's advisor. This is why,
to protect current  shareholders,  the fund's board of trustees decided to close
the Convertible Securities Fund.

STOCKS ROSE BUT WERE DOGGED BY INFLATIONARY FEARS

The fiscal  half-year  opened with strong  returns in the  domestic  and foreign
stock markets as the bull market of 2003 spilled into  January.  As the economic
expansion  gathered  momentum,  however,  concern about inflation and rising oil
prices  weighed on stock  prices.  Unrest in the Middle East and growing  global
demand  for oil  pushed  the  per-barrel  price past $40, a level not seen since
early in the  Iran-Iraq  War more than 20 years  ago.  In April,  stock  markets
retreated across the board.

For the six months,  the broad U.S.  stock market,  as measured by the Dow Jones
Wilshire  5000 Index,  returned  6.4%.  That return was  mirrored by the mid- to
large-capitalization stocks in the Russell 1000 Index; however, the Russell 2000
Index,  a proxy for  small-cap  stocks,  trailed  with a 4.5%  gain.  Across the
market-cap  spectrum,  value-oriented  stocks  (those  that  generally  trade at
below-market  valuations  relative  to their book  values and other  fundamental
measures)  posted better  results than growth stocks (those  expected to produce
above-average earnings growth).

For investors in the United States,  international  stocks  continued to provide
even better returns than the domestic market, a result of the relative  weakness
of the  U.S.  dollar  and the  solid  gains  of  stocks  in  Europe  and  Japan.

STRENGTHENING ECONOMY PUSHED BOND YIELDS HIGHER

In the fixed income markets, interest rates rose sharply in April in response to
signs of higher  inflation.  Over the six months  ended May 31, the yield of the
benchmark  10-year U.S.  Treasury note  increased 32 basis points to 4.65%.  The
Lehman Brothers Aggregate Bond Index, which covers the taxable  investment-grade
bond market,  returned  just 0.6%,  with income  offsetting  the price drop that
accompanies rising rates for bonds.

The yields of many short-term issues also rose in expectation of actions by the
Federal Reserve Board to boost interest rates, but for the shortest-

                                       2


- --------------------------------------------------------------------------------
MARKET BAROMETER                                                   TOTAL RETURNS
                                                      PERIODS ENDED MAY 31, 2004
                                                     ---------------------------
                                                         SIX       ONE      FIVE
                                                      MONTHS      YEAR    YEARS*
- --------------------------------------------------------------------------------
STOCK
Russell 1000 Index (Large-caps)                         6.4%     18.9%     -1.0%
Russell 2000 Index (Small-caps)                         4.5      30.3       6.7
Dow Jones Wilshire 5000 Index                           6.4      20.5      -0.5
   (Entire market)
MSCI All Country World Index
   ex USA (International)                               9.6      33.2       1.4
- --------------------------------------------------------------------------------
BOND
Lehman Aggregate Bond Index                             0.6%     -0.4%      6.8%
   (Broad taxable market)
Lehman Municipal Bond Index                            -0.2       0.0       5.5
Citigroup 3-Month Treasury Bill Index                   0.5       1.0       3.2
================================================================================
CPI
Consumer Price Index                                    2.5%      3.1%      2.6%
- --------------------------------------------------------------------------------
*Annualized.

term  securities--those  held by  money  market  funds--yields  were  relatively
stable.   These   securities   respond  more  to  Fed  actions  than  to  market
expectations.  The yield of the 3-month  Treasury bill, a proxy for money market
rates, started the half-year at 0.93% and ended at 1.06%.

A BELL-SHAPED PERFORMANCE CURVE FOR YOUR FUND

On the  way to its  3.1%  six-month  return,  the  Convertible  Securities  Fund
experienced considerable volatility.  The fund made strong gains in December and
January,  but gave up some of those  gains  during  the last two  months  of the
period. To an extent, that pattern mirrored what was happening in both the stock
and bond markets.  Convertibles,  by their nature, are linked to the performance
of the issuers' common stocks.

Your fund lagged the average return of  competitors  by 0.9 percentage  point, a
gap largely attributable to the nature of its holdings. As its name implies, the
fund invests almost  exclusively in convertible bonds and convertible  preferred
stocks.  This is in sharp  contrast to many of its peers.  Indeed,  according to
fund-tracker  Morningstar,  the average convertibles fund at the end of 2003 had
13% of its assets in common  stocks.  Your  fund's  disciplined  focus on hybrid
securities can place it at a disadvantage  when common stocks  outperform  other
asset classes,  and  particularly  when small-cap  growth stocks are lagging the
broad equity market, as they did during the fiscal  half-year.  Convertibles are
typically issued by small, growing companies.

The fund lagged its benchmark index by a wider margin of 1.5 percentage  points,
largely as a result of security selection.  We do not read too much into a track
record of just six months,  whether the record is stellar or subpar. In three of
the past four fiscal  years,  your fund  outpaced  its  benchmark  by much wider
margins. And the fund has outperformed its

                                       3


average  peer over the past  decade.  We believe  that the proven  skills of the
investment  advisor,  together  with  Vanguard's  low costs,  will help the fund
continue to post competitive returns over the long run.

For more information about the fund's performance and its individual securities,
please see the Report from the Advisor that begins on page 5.

NEW CONCERNS, SAME ADVICE

Not long ago, in the punishing bear market, we were counseling  investors not to
give up on stocks.  Today,  investor apprehension seems to have relocated to the
bond market, but our message is the same. The best response to the ever-changing
risks  of the  financial  markets  is to  develop  a plan and  stick  with it. A
sensible plan includes a mix of stock,  bond, and money market funds weighted in
proportions  appropriate  to your  unique  circumstances.  When a  tough  period
strikes one asset class, some of the pain can be offset by better performance in
another.  Over time, this simple,  balanced approach puts you in a good position
to meet your financial  goals.  Vanguard  Convertible  Securities Fund, with its
hybrid nature,  can play a useful role, adding another layer of  diversification
to such a balanced portfolio.

Thank you for entrusting your assets to us.

Sincerely,


/S/JOHN J. BRENNAN
John J. Brennan
CHAIRMAN AND CHIEF EXECUTIVE OFFICER

JUNE 14, 2004



- --------------------------------------------------------------------------------
YOUR FUND'S PERFORMANCE AT A GLANCE               NOVEMBER 30, 2003-MAY 31, 2004

                                                         DISTRIBUTIONS PER SHARE
                                                        ------------------------
                                    STARTING       ENDING      INCOME    CAPITAL
                                 SHARE PRICE  SHARE PRICE   DIVIDENDS      GAINS
- --------------------------------------------------------------------------------
Convertible Securities Fund           $13.05       $13.22       $0.23      $0.00
- --------------------------------------------------------------------------------

                                       4


REPORT FROM THE ADVISOR

Vanguard  Convertible  Securities  Fund  achieved a reasonable  absolute  return
during the first half of fiscal 2004, although our 3.1% gain fell slightly short
of the 4.6% returned by our primary benchmark,  the CS First Boston Convertibles
Index.  This  shortfall was due to the  underperformance  of a few  overweighted
positions in the latter part of the six-month period.  The absence from the fund
of a few of the index's  top-weighted  holdings  was also a factor,  since these
securities  performed  better than  expected,  especially  toward the end of the
period. Overall, though, we are pleased with the fund's result during what was a
very volatile market environment.

THE INVESTMENT ENVIRONMENT

Fiscal 2004 began where fiscal 2003 left off, with positive  investor  sentiment
for  equities  and lower  interest  rates  combining  to lift the prices of most
convertible  securities.  The beginning of the period was very positive for most
equities,  with the Nasdaq  Composite and Russell 2000 Indexes,  in  particular,
advancing  strongly.   During  this  time,   convertibles  from  technology  and
telecommunications  firms  were  the top  performers,  with  names  like  Lucent
Technologies,  Nortel Networks,  and Juniper Networks leading the way. Investors
also   exhibited  a   preference   for   small-capitalization   companies,   and
speculative-grade convertibles easily bested the investment-grade sector. On the
fixed  income side,  interest  rates  declined  slightly  while  credit  spreads
remained quite narrow;  these factors  boosted the prices of many  convertibles.
Nearly  all of our return for the  fiscal  half-year  came while this  favorable
environment existed.

- --------------------------------------------------------------------------------
INVESTMENT PHILOSOPHY

The advisor  believes  that a reasonable  level of current  income and long-term
growth in capital can be achieved by investing in a broadly diversified group of
convertible  securities that provide  attractive  combinations of current income
and  potential  for price  appreciation  from their  convertibility  into common
stock.
- --------------------------------------------------------------------------------

However,  the surge in  investor  optimism  was  short-lived,  as a  variety  of
negative  factors  began to affect the  financial  markets  beginning  in March:
Interest rates rose, credit spreads increased,

                                       5




oil prices increased to all-time highs, and the threat of terrorism intensified.
These and other concerns caused a significant  retreat in investor sentiment and
had a  negative  effect on all  convertibles,  including  most of our  holdings.
Despite  this  roller-coaster   investing   environment,   your  fund  performed
reasonably  well,  as our selling  discipline  and careful  new-issue  selection
allowed us to avoid several unfavorable situations.

Even with the  negative  market  overtones,  demand for  convertible  securities
remained  strong in recent months,  with interest  coming from a wide variety of
investors.  As a  result  of the  demand,  we  found  the  pricing  of many  new
convertibles  unattractive in terms of both yield and conversion  premiums.  The
size of the average new issue also  declined,  as very few  large-cap  companies
issued convertibles.

On  the  positive  side,  call  protection  became  quite  generous,   and  many
convertibles  provided short- to  intermediate-dated  put features. In addition,
dividend-protection  language became standard in response to the large number of
companies  initiating  or  increasing  their  dividends  on common  stock.  This
language is beneficial to convertibles  investors because dividend  increases on
the  underlying  common stock can have a negative  impact on the  valuation of a
convertible security. While we declined to participate in many new deals, we did
invest in  offerings  from  Fisher  Scientific  International,  Freeport-McMoRan
Copper & Gold, CP Ships,  and Chesapeake  Energy.  We expect the issuance of new
convertible securities to be moderate during the next few months.

THE FUND'S SUCCESSES

Some of our top performers were  convertibles from Fisher  Scientific,  Celgene,
J.C. Penney,  and American Tower.  Fisher is our top-weighted  holdings,  and we
remain very  positive  about its  underlying  equity  story;  we enjoy  balanced
convertible  exposure  to it  through  our  investments  in both  of the  firm's
convertible bonds. Other securities that performed  relatively well over the six
months include Royal Caribbean Cruises, Reliant Resources, and Flir Systems.

THE FUND'S SHORTFALLS

Several investments had disappointing  results,  primarily in the latter half of
the period, as negative developments affected their value.

                                       6


One high-profile  disappointment  was our position in the Nortel 4.25% converts,
which mature in September 2008. These bonds declined after the company announced
problems  in its  accounting  practices  and  fired  its  CEO and  CFO.  Valeant
Pharmaceuticals  International declined after reporting lackluster earnings. The
fund's limited airline industry exposure also was unrewarding, as the escalating
price of oil hurt airlines' near-term  profitability.  We continue to believe in
American  Airlines  and  Continental  Airlines  as  long-term  investments.

OUR POSITION

As usual, outside of a small short-term reserve, the portfolio consists entirely
of  convertibles--in  a  mix  of  83%  convertible  bonds  and  11%  convertible
preferreds--with no common stocks or other  nonconvertible  securities as of the
end of the  period.  We remain  positive  about the  investing  environment  and
believe we are well positioned to continue to achieve the fund's objectives.

Larry Keele, PORTFOLIO MANAGER
OAKTREE CAPITAL MANAGEMENT, LLC

June 16, 2004

                                       7



FUND PROFILE

AS OF 05/31/2004

This Profile provides a snapshot of the fund's  characteristics,  compared where
appropriate with a broad market index. Key terms are defined on pages 9 and 10.

CONVERTIBLE SECURITIES FUND
- --------------------------------------------
PORTFOLIO CHARACTERISTICS

Number of Securities                    104
Yield                                   2.7%
Conversion Premium                     51.2%
Average Weighted Maturity          5.0 years
Average Coupon                          3.3%
Average Quality                          BB-
Average Duration                   4.4 years
Foreign Holdings                       14.6%
Turnover Rate                          110%*
Expense Ratio                         0.71%*
Short-Term Reserves                       5%
- --------------------------------------------

- --------------------------------
DISTRIBUTION BY CREDIT QUALITY
(% OF FIXED INCOME PORTFOLIO)


Aaa/AAA                       0%
Aa/AA                         0
A/A                           7
Baa/BBB                      19
Ba/BB                         5
B/B                          36
Below B/B                    15
Not Rated                    18
- --------------------------------
Total                       100%
- --------------------------------

- --------------------------------------------
TEN LARGEST HOLDINGS (% OF TOTAL NET ASSETS)


Fisher Scientific International Inc.    4.5%
   (retail)
Teva Pharmaceutical Industries, Ltd.    3.5
  (pharmaceuticals)
Freeport-McMoRan Copper & Gold, Inc.    3.0
   (metals & mining)
Tyco International Group SA             3.0
   (conglomerate)
Invitrogen, Inc.                        3.0
   (pharmaceuticals)
Cephalon, Inc.                          2.9
   (pharmaceuticals)
Sealed Air Corp.                        2.8
   (industrial manufacturing)
Schlumberger Ltd.                       2.6
   (energy & utilities)
Valeant Pharmaceuticals International   2.1
   (pharmaceuticals)
Veeco Instruments, Inc.                 2.0
   (electronics)
- --------------------------------------------
Top Ten                                29.4%
- --------------------------------------------
"Ten Largest Holdings"  excludes any temporary cash investments and equity index
products.

- ---------------------------------------------------
VOLATILITY MEASURES
                                              BROAD
                                FUND        INDEX**
- ---------------------------------------------------
R-Squared                       0.67           1.00
Beta                            0.53           1.00
- ---------------------------------------------------

- ------------------------------------------------------
DISTRIBUTION BY MATURITY (% OF FIXED INCOME PORTFOLIO)

Under 1 Year                                        0%
1-5 Years                                          58
5-10 Years                                         42
10-20 Years                                         0
20-30 Years                                         0
Over 30 Years                                       0
- ------------------------------------------------------
Total                                             100%
- ------------------------------------------------------
 *Annualized.
**Dow Jones Wilshire 5000 Index.


                                               VISIT OUR WEBSITE AT VANGUARD.COM
                                         FOR REGULARLY UPDATED FUND INFORMATION.

                                       8




- ---------------------------------------
SECTOR DIVERSIFICATION (% OF PORTFOLIO)

Auto & Transportation               10%
Consumer Discretionary              14
Financial Services                   8
Health Care                         19
Other Energy                         9
Materials & Processing               9
Producer Durables                    0
Technology                          18
Utilities                            5
Other                                3
Short-Term Reserves                  5%
- ---------------------------------------



GLOSSARY OF INVESTMENT TERMS

AVERAGE COUPON.  The average  interest rate paid on the fixed income  securities
held by a fund. It is expressed as a percentage of face value.
- --------------------------------------------------------------------------------
AVERAGE DURATION.  An estimate of how much the value of the bonds held by a fund
will fluctuate in response to a change in interest  rates.  To see how the value
could change,  multiply the average duration by the change in rates. If interest
rates  rise by 1  percentage  point,  the  value of the  bonds in a fund with an
average duration of five years would decline by about 5%. If rates decrease by a
percentage point, the value would rise by 5%.
- --------------------------------------------------------------------------------
AVERAGE QUALITY.  An indicator of credit risk, this figure is the average of the
ratings  assigned to a fund's holdings by credit-rating  agencies.  The agencies
make  their  judgment  after   appraising  an  issuer's   ability  to  meet  its
obligations.  Quality is graded on a scale,  with Aaa or AAA indicating the most
creditworthy bond issuers.
- --------------------------------------------------------------------------------
AVERAGE  WEIGHTED  MATURITY.  The  average  length of time  until  fixed  income
securities held by a fund reach maturity and are repaid. The figure reflects the
proportion of fund assets represented by each security.
- --------------------------------------------------------------------------------

                                       9

GLOSSARY OF INVESTMENTS TERMS (CONTINUED)

- --------------------------------------------------------------------------------
BETA. A measure of the magnitude of a fund's past  share-price  fluctuations  in
relation to the ups and downs of a given market  index.  The index is assigned a
beta of 1.00.  Compared with a given index, a fund with a beta of 1.20 typically
would have seen its share  price rise or fall by 12% when the index rose or fell
by 10%. A fund's beta should be reviewed in conjunction  with its R-squared (see
definition  below).  The  lower the  R-squared,  the less  correlation  there is
between the fund and the index, and the less reliable beta is as an indicator of
volatility.
- --------------------------------------------------------------------------------
CONVERSION PREMIUM.  The average percentage by which the weighted average market
price of the convertible  securities held by a fund exceeds the weighted average
market price of their  underlying  common  stocks.  For  example,  if a stock is
trading at $25 per share and a bond  convertible  into the stock is trading at a
price equivalent to $30 per share of stock, the conversion  premium is 20% ($5 /
$25 = 20%).
- --------------------------------------------------------------------------------
EXPENSE  RATIO.  The  percentage of a fund's  average net assets used to pay its
annual  administrative  and advisory  expenses.  These expenses  directly reduce
returns to investors.
- --------------------------------------------------------------------------------
FOREIGN  HOLDINGS.  The  percentage  of  a  fund's  net  assets  represented  by
securities of companies based outside the United States.
- --------------------------------------------------------------------------------
R-SQUARED.  A measure of how much of a fund's past  returns can be  explained by
the returns  from the market in general,  as  measured  by a given  index.  If a
fund's total returns were precisely  synchronized  with an index's returns,  its
R-squared  would be 1.00.  If the fund's  returns  bore no  relationship  to the
index's returns, its R-squared would be 0.
- --------------------------------------------------------------------------------
SHORT-TERM  RESERVES.  The  percentage  of a fund  invested  in  highly  liquid,
short-term securities that can be readily converted to cash.
- --------------------------------------------------------------------------------
TURNOVER  RATE. An indication of the fund's  trading  activity.  Funds with high
turnover  rates  incur  higher  transaction  costs  and  may be more  likely  to
distribute capital gains (which may be taxable to investors).
- --------------------------------------------------------------------------------
YIELD.  A snapshot of a fund's  income from interest and  dividends.  The yield,
expressed  as a  percentage  of the fund's net asset  value,  is based on income
earned over the past 30 days and is  annualized,  or  projected  forward for the
coming year.
- --------------------------------------------------------------------------------

                                       10


PERFORMANCE SUMMARY

AS OF 5/31/2004

All of the returns in this report  represent  past  performance,  which is not a
guarantee  of future  results  that may be achieved  by the fund.  (For the most
recent  performance,  which may be higher or lower  than that  cited,  visit our
website at  www.vanguard.com.)  Note,  too,  that both  investment  returns  and
principal value can fluctuate widely, so an investor's shares,  when sold, could
be worth more or less than their original cost. The returns shown do not reflect
taxes that a shareholder would pay on fund  distributions or on the sale of fund
shares.

CONVERTIBLE SECURITIES FUND
- --------------------------------------------------------------------------------
FISCAL-YEAR TOTAL RETURNS (%) NOVEMBER 30, 1993-MAY 31, 2004

                      CONVERTIBLE           CS FIRST BOSTON
                    SECURITIES FUND        CONVERTIBLE INDEX

1994                     -4.4                    -3.9
1995                     17.1                    24.0
1996                     14.9                    15.3
1997                     14.8                    15.4
1998                     -2.2                     1.4
1999                     24.8                    30.6
2000                      5.3                     1.5
2001                      4.0                    -3.6
2002                     -8.9                    -5.9
2003                     28.1                    23.7
2004*                     3.1                     4.6
- --------------------------------------------------------------------------------
*Six months ended May 31, 2004.
NOTE: See Financial  Highlights  table on page 20 for dividend and capital gains
information.

- --------------------------------------------------------------------------------
AVERAGE ANNUAL TOTAL RETURNS FOR PERIODS ENDED MARCH 31, 2004

This table  presents  average annual total returns  through the latest  calendar
quarter--rather  than  through  the end of the  fiscal  period.  Securities  and
Exchange Commission rules require that we provide this information.

                                                                TEN YEARS
                                             ONE      FIVE  --------------------
                           INCEPTION DATE   YEAR     YEARS  CAPITAL INCOME TOTAL
- --------------------------------------------------------------------------------
Convertible Securities Fund     6/17/1986 34.21%    10.77%    5.20%  4.52% 9.72%
- --------------------------------------------------------------------------------

                                       11



ABOUT YOUR FUND'S EXPENSES

We believe it is  important  for you to  understand  the impact of costs on your
investment.  All mutual funds have operating  expenses.  As a shareholder of the
fund,  you incur ongoing  costs,  which include costs for portfolio  management,
administrative  services, and shareholder reports (like this one), among others.
Operating  expenses,  which are deducted  from a fund's gross  income,  directly
reduce the investment return of the fund.

A fund's expenses are expressed as a percentage of its average net assets.  This
figure is known as the expense  ratio.  The  following  examples are intended to
help you understand the ongoing costs (in dollars) of investing in your fund and
to compare these costs with those of other mutual funds.  The examples are based
on an  investment  of $1,000 made at the  beginning of the period shown and held
for the entire period.

The table below illustrates your fund's costs in two ways:

*    ACTUAL FUND RETURN.  This section helps you to estimate the actual expenses
     that you paid over the period.  The "Ending Account Value" shown is derived
     from the fund's actual return, and the third column shows the dollar amount
     that would have been paid by an  investor  who  started  with $1,000 in the
     fund.  You may use the  information  here,  together  with the  amount  you
     invested, to estimate the expenses that you paid over the period.

     To do so,  simply  divide your  account  value by $1,000 (for  example,  an
     $8,600 account value divided by $1,000 = 8.6),  then multiply the result by
     the number  given for your fund under the  heading  "Expenses  Paid  During
     Period."

*    Hypothetical  5% return.  This section is intended to help you compare your
     fund's costs with those of other mutual funds. It assumes that the fund had
     a return  of 5% before  expenses  during  the  period  shown,  but that the
     expense ratio is unchanged.  In this  case--because  the return used is not
     the fund's actual return--the results do not apply to your investment.  The
     example is useful in making comparisons because the Securities and Exchange
     Commission  requires all mutual funds to calculate  expenses  based on a 5%
     return.  You can assess your fund's  costs by comparing  this  hypothetical
     example with the hypothetical  examples that appear in shareholder  reports
     of other funds.

- --------------------------------------------------------------------------------
SIX MONTHS ENDED MAY 31, 2004
                                BEGINNING              ENDING           EXPENSES
CONVERTIBLE                 ACCOUNT VALUE       ACCOUNT VALUE        PAID DURING
SECURITIES FUND                11/30/2003           5/31/2004            PERIOD*
- --------------------------------------------------------------------------------
Actual Fund Return                 $1,000              $1,031              $3.61
Hypothetical 5% Return              1,000               1,046               3.63
- --------------------------------------------------------------------------------
*Expenses are equal to the fund's  annualized  expense  ratio  multiplied by the
average  account value over the period,  multiplied by the number of days in the
most recent fiscal half-year, then divided by 366.


Note that the expenses  shown in the table are meant to  highlight  and help you
compare ongoing costs only and do not reflect any transactional costs or account
maintenance fees. They do not include your fund's  low-balance fee, described in
the  prospectus.  If this fee were applied to your account,  your costs would be
higher.  Your  fund  does not  charge  transaction  fees,  such as  purchase  or
redemption fees, nor does it carry a "sales load."

                                       12


- -------------------------------------------------------------
ANNUALIZED EXPENSE RATIOS:
YOUR FUND COMPARED WITH ITS PEER GROUP
                                                      AVERAGE
                                                  CONVERTIBLE
                                                   SECURITIES
                                     FUND                FUND
- -------------------------------------------------------------
Convertible Securities Fund         0.71%              1.64%*
- -------------------------------------------------------------
Peer-group  expense  ratio is derived  from data  provided by Lipper  Inc.  and
captures information through year-end 2003.

The  calculations  assume no shares were bought or sold during the period.  Your
actual  costs may have been  higher or lower,  depending  on the  amount of your
investment and the timing of any purchases or redemptions.

You can find  more  information  about the  fund's  expenses,  including  annual
expense ratios for the past five years, in the Financial  Statements  section of
this  report.  For  additional  information  on  operating  expenses  and  other
shareholder costs, please refer to the appropriate fund prospectus.

                                       13


FINANCIAL STATEMENTS (UNAUDITED)

AS OF 5/31/2004


STATEMENT OF NET ASSETS

This Statement  provides a detailed list of the fund's holdings,  including each
security's market value on the last day of the reporting period.  Securities are
grouped  and  subtotaled  by asset  type  (common  stocks,  bonds,  etc.) and by
industry sector. Other assets are added to, and liabilities are subtracted from,
the value of Total Investments to calculate the fund's Net Assets.  Finally, Net
Assets are divided by the outstanding  shares of the fund to arrive at its share
price, or Net Asset Value (NAV) Per Share.

At the end of the Statement of Net Assets,  you will find a table displaying the
composition of the fund's net assets.  Because all income and any realized gains
must be distributed to  shareholders  each year, the bulk of net assets consists
of Paid-in  Capital  (money  invested by  shareholders).  The amounts  shown for
Undistributed  Net Investment  Income and Accumulated Net Realized Gains usually
approximate  the sums the fund had available to distribute  to  shareholders  as
income  dividends  or capital  gains as of the  statement  date,  but may differ
because  certain  investments or  transactions  may be treated  differently  for
financial  statement and tax purposes.  Any Accumulated Net Realized Losses, and
any cumulative  excess of  distributions  over net income or net realized gains,
will appear as negative balances.  Unrealized Appreciation (Depreciation) is the
difference  between the market value of the fund's  investments  and their cost,
and reflects the gains  (losses) that would be realized if the fund were to sell
all of its investments at their statement-date values.


- --------------------------------------------------------------------------------
                                                      FACE                MARKET
                                                    AMOUNT                VALUE*
CONVERTIBLE SECURITIES FUND                          (000)                 (000)
- --------------------------------------------------------------------------------
CONVERTIBLE BONDS (83.4%)
- --------------------------------------------------------------------------------
AUTO & TRANSPORTATION (9.9%)
American Airlines
     4.25%, 9/23/2023                        $      16,345         $     14,751
Continental Airlines, Inc.
     4.50%, 2/1/2007                                17,300               12,802
(1)  5.00%, 6/15/2023                                1,240                1,018
CP Ships Ltd.
(1)  4.00%, 6/30/2024                               18,655               19,215
General Motors Corp.
     5.25%, 3/6/2032                                   754               18,350
Lear Corp.
     0.00%, 2/20/2022                               18,730                9,623
Mesa Air Group Inc.
(1)  2.482%, 6/16/2023                               6,250                2,758
Navistar Financial Corp.
     4.75%, 4/1/2009                                17,600               17,160
Northwest Airlines Corp.
(1)  7.625%, 11/15/2023                             12,890               10,070
                                                                   -------------
                                                                   $    105,747
                                                                   -------------
CONSUMER DISCRETIONARY (12.6%)

Charming Shoppes, Inc.
     4.75%, 6/1/2012                                 2,960                3,397
Citadel Broadcasting Co.
(1)  1.875%, 2/15/2011                               4,375                3,894
The Walt Disney Co.
     2.125%, 4/15/2023                              11,930               12,482
Echostar Communications Corp.
     5.75%, 5/15/2008                                4,795                4,885
Fairmont Hotels
(1)  3.75%, 12/1/2023                               13,365               13,098
IKON Office Solutions, Inc.
(1)  5.00%, 5/1/2007                                 1,600                1,686
Lamar Advertising Co.
     2.875%, 12/31/2010                             10,320               10,836
Liberty Media Corp.
(1)  0.75%, 3/30/2023                               11,180               12,536
Lowe's Cos., Inc.
     0.861%, 10/19/2021                             10,030               10,293
Memberworks, Inc.
(1)  5.50%, 10/1/2010                                5,330                5,430
NCO Group, Inc.
     4.75%, 4/15/2006                                8,407                8,638
News America Inc.
     0.00%, 2/28/2021                               18,080               10,373
Aristocrat Leisure Ltd.
     5.00%, 5/31/2006                                7,300                7,738
Shuffle Master, Inc.
(1)  1.25%, 4/15/2024                                7,300                7,501
Sirius Satellite Radio
(1)  2.50%, 2/15/2009                               10,600               10,454
Triarc Cos., Inc.
(1)  5.00%, 5/15/2023                                4,448                4,543
     5.00%, 5/15/2023                                1,520                1,552

                                       14



- --------------------------------------------------------------------------------
                                                      FACE                MARKET
                                                    AMOUNT                VALUE*
CONVERTIBLE SECURITIES FUND                          (000)                 (000)
- --------------------------------------------------------------------------------
Waste Connections, Inc.
     1.678%, 5/1/2022                        $       4,635         $      5,000
                                                                   -------------
                                                                   $    134,336
                                                                   -------------
FINANCIAL SERVICES (4.8%)
HCC Insurance Holdings, Inc.
     1.30%, 4/1/2023                                13,780               14,882
Meristar Hospitality Corp.
     9.50%, 4/1/2010                                 6,420                7,664
Ohio Casualty Corp.
     5.00%, 3/19/2022                               15,545               16,109
Providian Financial Corp.
     3.25%, 8/15/2005                                7,290                7,117
United Rentals NA Inc.
(1)  1.875%, 10/15/2023                              5,700                5,379
                                                                   -------------
                                                                   $     51,151
                                                                   -------------
HEALTH CARE (18.8%)
Cephalon, Inc.
     2.50%, 12/15/2006                              22,590               21,828
     0.00%, 6/15/2033                                8,215                8,595
Community Health Systems, Inc.
     4.25%, 10/15/2008                              18,300               18,758
Connetics Corp.
     2.25%, 5/30/2008                                9,630               11,135
Decode Genetics, Inc.
(1)  3.50%, 4/15/2011                                3,620                3,462
Imclone Systems
(1)  1.375%, 5/15/2024                               9,310               10,032
Invitrogen Inc.
     2.25%, 12/15/2006                              30,645               31,718
Oscient Pharmaceuticals
(1)  3.50%, 4/15/2011                                2,055                2,016
Sunrise Assisted Living, Inc.
(1)  5.25%, 2/1/2009                                 1,570                1,839
     5.25%, 2/1/2009                                13,430               15,730
Teva Pharmaceutical Finance II
     0.25%, 2/1/2024                                24,035               25,357
     0.50%, 2/1/2024                                11,415               11,815
Valeant Pharmaceuticals International
(1)  3.00%, 8/16/2010                               14,160               12,903
(1)  4.00%, 11/15/2013                              10,425                9,604
Wyeth
(1)  0.716%, 7/15/2004                              15,930               15,691
                                                                   -------------
                                                                   $    200,483
                                                                   -------------
OTHER ENERGY (6.1%)

Hanover Compressor Co.
     4.75%, 3/15/2008                                3,240                3,013
     4.75%, 1/15/2014                                3,970                4,183
Massey Energy Co.
(1)  2.25%, 4/1/2024                                11,445               11,774
Reliant Resources, Inc.
(1)  5.00%, 8/15/2010                               14,040               18,585
Schlumberger Ltd.
     1.50%, 6/1/2023                                27,035               27,609
                                                                   -------------
                                                                   $     65,164
                                                                   -------------
MATERIALS & PROCESSING (5.9%)
Fluor Corp.
     1.50%, 2/15/2024                               19,140               18,853
Graftech International
(1)  1.625%, 1/15/2024                              16,355               14,106
Sealed Air Corp.
(1)  3.00%, 6/30/2033                               29,935               29,898
                                                                   -------------
                                                                   $     62,857
                                                                   -------------
PRODUCER DURABLES (0.2%)
Lam Research Corp.
     4.00%, 6/1/2006                                 1,725                1,738

TECHNOLOGY (17.3%)
ADC Telecommunications, Inc.
     1.00%, 6/15/2008                                2,815                2,674
Axcelis Technologies
     4.25%, 1/15/2007                                9,865                9,728
CIBER INC.
(1)  2.875%, 12/15/2023                             14,755               14,405
Commscope Inc.
(1)  1.00%, 3/15/2024                               10,350               10,415
EDO Corp.
(1)  5.25%, 4/15/2007                                  745                  765
     5.25%, 4/15/2007                                1,000                1,028
EMC Corp.
(1)  4.50%, 4/1/2007                                 2,760                3,022
FEI Co.
(1)  0.00%, 6/15/2023                                3,000                3,364
     0.00%, 6/15/2023                                  190                  213
Flir Systems, Inc.
(1)  3.00%, 6/1/2023                                 8,515               11,304
     3.00%, 6/1/2023                                 3,115                4,135
Fisher Scientific International Inc.
(1)  2.50%, 10/1/2023                               16,720               23,492
     2.50%, 10/1/2023                                  910                1,279
     3.25%, 3/1/2024                                22,775               23,458
HNC Software Inc.
     5.25%, 9/1/2008                                   755                  804
International Rectifier Corp.
     4.25%, 7/15/2007                               15,705               15,273

                                       15



- --------------------------------------------------------------------------------
                                                      FACE                MARKET
                                                    AMOUNT                VALUE*
CONVERTIBLE SECURITIES FUND                          (000)                 (000)
- --------------------------------------------------------------------------------
LSI Logic
(1)  4.00%, 5/15/2010                        $       8,655         $      8,980
     4.00%, 5/15/2010                                1,740                1,805
Mercury Computer Systems
(1)  2.00%, 5/1/2009                                 8,010                8,150
Nortel Networks Corp.
     4.25%, 9/1/2008 11,655 10,519
Photronics, Inc.
     4.75%, 12/15/2006 1,386 1,377
Serena Software, Inc.
(1)  1.50%, 12/15/2023 2,130 2,435
Solectron Corp.
(1)  0.50%, 2/15/2034 4,225 3,538
Veeco Instruments, Inc.
     4.125%, 12/21/2008 21,709 21,818
                                                                   -------------
                                                                   $    183,981
                                                                   -------------
UTILITIES (4.8%)
American Tower Corp.
(1)  3.25%, 8/1/2010                                 8,430               11,560
     3.25%, 8/1/2010                                 3,940                5,403
Mediacom Communications Corp.
     5.25%, 7/1/2006                                 3,650                3,458
NII Holdings
(1)  2.875%, 2/1/2034                               10,500               10,671
Primus Telecommunications Group, Inc.
(1)  3.75%, 9/15/2010                                2,415                2,433
     3.75%, 9/15/2010                                1,325                1,334
     5.75%, 2/15/2007                               11,305               10,754
Quanta Services, Inc.
(1)  4.50%, 10/1/2023                                5,535                5,237
                                                                   -------------
                                                                   $     50,850
                                                                   -------------
OTHER (3.0%)
Tyco International Group SA
(1)  2.75%, 1/15/2018                               16,580               23,544
     2.75%, 1/15/2018                                5,850                8,307
                                                                   -------------
                                                                   $     31,851
                                                                   -------------
- --------------------------------------------------------------------------------
TOTAL CONVERTIBLE BONDS
     (Cost $878,874)                                               $    888,158
- --------------------------------------------------------------------------------


- --------------------------------------------------------------------------------
                                                                         MARKET
                                                                         VALUE*
                                                    SHARES                (000)
- --------------------------------------------------------------------------------
CONVERTIBLE PREFERRED STOCKS (11.3%)
- --------------------------------------------------------------------------------
CONSUMER DISCRETIONARY (1.3%)
Interpublic Group
     5.375% Cvt. Pfd.                              203,300         $     10,698
Emmis Communications Corp.
     6.25% Cvt. Pfd.                                63,300                2,900
                                                                   -------------
                                                                   $     13,598
                                                                   -------------
FINANCIAL SERVICES (3.1%)
Conseco Inc.
     5.50% Cvt. Pfd.                               334,600                8,700
Commerce Capital
     5.95% Cvt. Pfd.                               119,500                7,678
(1)  5.95% Cvt. Pfd.                                31,400                2,017
Reinsurance Group of America
     5.75% Cvt. Pfd.                                65,000                3,702
United Rentals
     6.50% Cvt. Pfd.                               171,100                7,421
Washington Mutual, Inc.
(1)  5.375% Cvt. Pfd.                               58,000                3,346
                                                                   -------------
                                                                   $     32,864
                                                                   -------------
OTHER ENERGY (2.7%)

Chesapeake Energy Corp.
(1)  4.125% Cvt. Pfd.                               13,900               13,970
     5.00% Cvt. Pfd.                                66,100                6,924
Hanover Compressor Capital Trust
     7.25% Cvt. Pfd.                               168,200                7,863
                                                                   -------------
                                                                   $     28,757
                                                                   -------------
MATERIALS & PROCESSING (3.0%)
Freeport-McMoRan Copper & Gold, Inc.
(1)  5.50% Cvt. Pfd.                                35,400               31,993

TECHNOLOGY (1.0%)
Lucent Technologies Capital Trust I
     7.75% Cvt. Pfd.                                 9,600               10,960

UTILITIES (0.2%)
Dominion Resources, Inc.
     9.50% Cvt. Pfd.                               46,900                 2,548
                                                                   -------------
- --------------------------------------------------------------------------------
TOTAL CONVERTIBLE PREFERRED STOCKS
     (Cost $117,821)                                               $    120,720
- --------------------------------------------------------------------------------

                                       16



- --------------------------------------------------------------------------------
                                                      FACE                MARKET
                                                    AMOUNT                VALUE*
                                                     (000)                 (000)
- --------------------------------------------------------------------------------
TEMPORARY CASH INVESTMENTS (27.0%)
- --------------------------------------------------------------------------------
REPURCHASE AGREEMENTS
Collateralized by U.S. Government
     Obligations in a Pooled
     Cash Account
     1.03%, 6/1/2004                         $      57,789         $     57,789
     1.03%, 6/1/2004--Note F                       229,766              229,766
- --------------------------------------------------------------------------------
TOTAL TEMPORARY CASH INVESTMENTS
     (Cost $287,555)                                               $    287,555
- --------------------------------------------------------------------------------
TOTAL INVESTMENTS (121.7%)
     (Cost $1,284,250)                                             $  1,296,433
- --------------------------------------------------------------------------------
OTHER ASSETS AND LIABILITIES (-21.7%)
- --------------------------------------------------------------------------------
Other Assets--Note C                                                     15,118
Security Lending Collateral
     Payable to Brokers--Note F                                        (229,766)
Other Liabilities                                                       (16,493)
                                                                   -------------
                                                                   $   (231,141)
                                                                   -------------
- --------------------------------------------------------------------------------
NET ASSETS (100%)
- --------------------------------------------------------------------------------
Applicable to 80,601,080 outstanding $.001
  par value shares of beneficial interest
     (unlimited authorization)                                     $  1,065,292
================================================================================

NET ASSET VALUE PER SHARE                                          $      13.22
================================================================================
*See Note A in Notes to Financial Statements.
(1) Securities exempt from registration under Rule 144A of the Securities Act of
1933.  These  securities may be sold in transactions  exempt from  registration,
normally to qualified institutional buyers. At May 31, 2004, the aggregate value
of these securities was $422,133,000, representing 40.0% of net assets.

- -------------------------------------------------------------------
                                                    AMOUNT      PER
                                                     (000)    SHARE
- -------------------------------------------------------------------
AT MAY 31, 2004, NET ASSETS CONSISTED OF:
- -------------------------------------------------------------------
Paid-in Capital                              $   1,010,565  $ 12.54
Undistributed Net
  Investment Income                                  4,843      .06
Accumulated Net
  Realized Gains                                    37,701      .47
Unrealized Appreciation                             12,183      .15
- -------------------------------------------------------------------
NET ASSETS                                   $   1,065,292  $ 13.22
===================================================================
See Note D in Notes to Financial  Statements for the tax-basis components of net
assets.

                                       17


STATEMENT OF OPERATIONS

This Statement shows the types of income earned by the fund during the reporting
period,  and details the operating  expenses charged to the fund. These expenses
directly reduce the amount of investment income available to pay to shareholders
as income  dividends.  This Statement also shows any Net Gain (Loss) realized on
the  sale of  investments,  and  the  increase  or  decrease  in the  Unrealized
Appreciation (Depreciation) of investments during the period.

- --------------------------------------------------------------------------------
                                                     CONVERTIBLE SECURITIES FUND
                                                   SIX MONTHS ENDED MAY 31, 2004
                                                                           (000)
- --------------------------------------------------------------------------------
INVESTMENT INCOME
INCOME
  Dividends                                                        $      2,928
  Interest                                                               15,802
  Security Lending                                                          319
- --------------------------------------------------------------------------------
    Total Income                                                   $     19,049
- --------------------------------------------------------------------------------
EXPENSES
  Investment Advisory Fees--Note B
    Basic Fee                                                             1,822
    Performance Adjustment                                                  442
  The Vanguard Group--Note C
    Management and Administrative                                         1,254
    Marketing and Distribution                                               63
  Custodian Fees                                                              8
  Shareholders' Reports                                                      13
  Trustees' Fees and Expenses                                                 1
- --------------------------------------------------------------------------------
    Total Expenses                                                 $      3,603
- --------------------------------------------------------------------------------
NET INVESTMENT INCOME                                                    15,446
- --------------------------------------------------------------------------------
REALIZED NET GAIN (LOSS) ON INVESTMENT SECURITIES SOLD                   53,708
- --------------------------------------------------------------------------------
CHANGE IN UNREALIZED APPRECIATION (DEPRECIATION)
    OF INVESTMENT SECURITIES                                            (52,747)
- --------------------------------------------------------------------------------
NET INCREASE (DECREASE) IN NET ASSETS RESULTING FROM OPERATIONS    $     16,407
================================================================================

                                       18



STATEMENT OF CHANGES IN NET ASSETS

This Statement shows how the fund's total net assets changed during the two most
recent reporting periods. The Operations section summarizes information detailed
in  the  Statement  of  Operations.   The  amounts  shown  as  Distributions  to
shareholders  from the fund's net  income  and  capital  gains may not match the
amounts shown in the Operations section, because distributions are determined on
a tax  basis  and may be made in a period  different  from the one in which  the
income was earned or the gains were  realized on the financial  statements.  The
Capital Share Transactions section shows the amount shareholders invested in the
fund,  either by purchasing shares or by reinvesting  distributions,  as well as
the amounts redeemed.  The  corresponding  numbers of Shares Issued and Redeemed
are shown at the end of the Statement.

- --------------------------------------------------------------------------------
                                                CONVERTIBLE SECURITIES FUND
                                             -----------------------------------
                                                SIX MONTHS                  YEAR
                                                     ENDED                 ENDED
                                              MAY 31, 2004         NOV. 30, 2003
                                                     (000)                 (000)
- --------------------------------------------------------------------------------
INCREASE (DECREASE) IN NET ASSETS
OPERATIONS
  Net Investment Income                      $      15,446         $     19,841
  Realized Net Gain (Loss)                          53,708               61,788
  Change in Unrealized Appreciation
    (Depreciation)                                 (52,747)              59,263
- --------------------------------------------------------------------------------
    Net Increase (Decrease) in Net Assets
      Resulting from Operations                     16,407              140,892
- --------------------------------------------------------------------------------
DISTRIBUTIONS
  Net Investment Income                            (16,127)             (16,869)
  Realized Capital Gain                                 --                   --
- --------------------------------------------------------------------------------
    Total Distributions                            (16,127)             (16,869)
- --------------------------------------------------------------------------------
CAPITAL SHARE TRANSACTIONS1
  Issued                                           392,028              515,418
  Issued in Lieu of Cash Distributions              13,735               14,331
  Redeemed                                        (157,941)            (127,279)
- --------------------------------------------------------------------------------
    Net Increase (Decrease) from Capital
      Share Transactions                           247,822              402,470
- --------------------------------------------------------------------------------
  Total Increase (Decrease)                        248,102              526,493
- --------------------------------------------------------------------------------

NET ASSETS
  Beginning of Period                              817,190              290,697
- --------------------------------------------------------------------------------
  End of Period                              $   1,065,292         $    817,190
================================================================================

1Shares Issued (Redeemed)
  Issued                                            28,733               44,868
  Issued in Lieu of Cash Distributions               1,032                1,265
  Redeemed                                         (11,807)             (10,983)
- --------------------------------------------------------------------------------
    Net Increase (Decrease) in Shares
     Outstanding                             $      17,958         $     35,150
================================================================================

                                       19




FINANCIAL HIGHLIGHTS

This table  summarizes  the  fund's  investment  results  and  distributions  to
shareholders  on a per-share  basis. It also presents the Total Return and shows
net investment  income and expenses as percentages of average net assets.  These
data will help you assess:  the  variability  of the fund's net income and total
returns from year to year; the relative  contributions of net income and capital
gains to the fund's total return; how much it costs to operate the fund; and the
extent to which the fund tends to distribute capital gains. The table also shows
the Portfolio  Turnover Rate, a measure of trading activity.  A turnover rate of
100% means that the average security is held in the fund for one year.



CONVERTIBLE SECURITIES FUND
- --------------------------------------------------------------------------------------------------------------
                                          SIX MONTHS ENDED         YEAR ENDED NOVEMBER 30,
                                                   MAY 31, ---------------------------------------------------
                                                                                    
FOR A SHARE OUTSTANDING THROUGHOUT EACH PERIOD       2004      2003        2002      2001       2000      1999
- --------------------------------------------------------------------------------------------------------------
NET ASSET VALUE, BEGINNING OF PERIOD                $13.05   $10.57      $12.12    $12.68     $13.18   $11.10
- --------------------------------------------------------------------------------------------------------------
INVESTMENT OPERATIONS
  Net Investment Income                                .20      .41         .47       .53        .56      .52
  Net Realized and Unrealized Gain (Loss)
    on Investments                                     .20     2.48       (1.53)     (.04)       .19     2.13
- --------------------------------------------------------------------------------------------------------------
  Total from Investment Operations                     .40     2.89       (1.06)      .49        .75     2.65
- --------------------------------------------------------------------------------------------------------------
DISTRIBUTIONS
  Dividends from Net Investment Income                (.23)    (.41)       (.49)     (.54)      (.55)    (.57)
  Distributions from Realized Capital Gains           . --     . --        . --      (.51)      (.70)    . --
- --------------------------------------------------------------------------------------------------------------
    Total Distributions                               (.23)    (.41)       (.49)    (1.05)     (1.25)    (.57)
- --------------------------------------------------------------------------------------------------------------

NET ASSET VALUE, END OF PERIOD                      $13.22   $13.05      $10.57    $12.12     $12.68   $13.18
==============================================================================================================

TOTAL RETURN                                         3.06%   28.07%      -8.88%     3.98%      5.27%   24.85%
==============================================================================================================

RATIOS/SUPPLEMENTAL DATA

  Net Assets, End of Period (Millions)              $1,065     $817        $291      $300       $323     $180
  Ratio of Total Expenses to Average Net Assets*   0.71%**    0.84%       0.95%     0.71%      0.56%    0.55%
  Ratio of Net Investment Income to
   Average Net Assets                              3.03%**    3.82%       4.27%     4.21%      4.19%    4.30%
  Portfolio Turnover Rate                           110%**     127%        118%      156%       182%     162%
==============================================================================================================
* Includes  performance-based  investment advisory fee increases  (decreases) of
0.09%, 0.13%, 0.21%, 0.01%, (0.14%), and (0.22%).
**Annualized.


SEE ACCOMPANYING NOTES, WHICH ARE AN INTEGRAL PART OF THE FINANCIAL STATEMENTS.

                                       20


NOTES TO FINANCIAL STATEMENTS

Vanguard Convertible  Securities Fund is registered under the Investment Company
Act of 1940 as an open-end investment company, or mutual fund.

A. The following  significant  accounting policies conform to generally accepted
accounting  principles for U.S. mutual funds. The fund consistently follows such
policies in preparing its financial statements.

     1. SECURITY VALUATION:  Securities are valued as of the close of trading on
the New York Stock Exchange  (generally 4:00 p.m. Eastern time) on the valuation
date. Equity securities are valued at the latest quoted sales prices or official
closing prices taken from the primary market in which each security trades; such
securities not traded on the valuation date are valued at the mean of the latest
quoted bid and asked prices. Bonds, and temporary cash investments acquired over
60 days to maturity,  are valued using the latest bid prices or using valuations
based on a matrix  system  (which  considers  such  factors as security  prices,
yields,  maturities,  and  ratings),  both as furnished by  independent  pricing
services.  Other temporary cash  investments are valued at amortized cost, which
approximates  market  value.  Securities  for which  market  quotations  are not
readily  available,  or whose  values  have been  materially  affected by events
occurring  before the fund's pricing time but after the close of the securities'
primary  markets,  are  valued by  methods  deemed by the board of  trustees  to
represent fair value.

     2.  REPURCHASE  AGREEMENTS:  The fund,  along  with  other  members  of The
Vanguard Group,  transfers  uninvested cash balances into a pooled cash account,
which  is  invested  in  repurchase   agreements  secured  by  U.S.   government
securities.  Securities pledged as collateral for repurchase agreements are held
by a custodian bank until the agreements  mature.  Each agreement  requires that
the market value of the  collateral be sufficient to cover  payments of interest
and principal; however, in the event of default or bankruptcy by the other party
to  the  agreement,  retention  of  the  collateral  may  be  subject  to  legal
proceedings.

     3.  FEDERAL  INCOME  TAXES:  The fund  intends to  continue to qualify as a
regulated   investment  company  and  distribute  all  of  its  taxable  income.
Accordingly,  no provision for federal income taxes is required in the financial
statements.

     4.  DISTRIBUTIONS:  Distributions  to  shareholders  are  recorded  on  the
ex-dividend date.

     5. OTHER:  Dividend  income is recorded on the ex-dividend  date.  Security
transactions  are accounted for on the date the  securities  are bought or sold.
Costs  used to  determine  realized  gains  (losses)  on the sale of  investment
securities are those of the specific  securities sold. Premiums and discounts on
debt securities purchased are amortized and accreted,  respectively, to interest
income over the lives of the respective securities.

B. Oaktree Capital Management, LLC, provides investment advisory services to the
fund for a fee  calculated at an annual  percentage  rate of average net assets.
The  basic  fee  is  subject  to  quarterly  adjustments  based  on  the  fund's
performance  for the preceding  three years  relative to the Credit Suisse First
Boston Convertible  Securities Index. For the six months ended May 31, 2004, the
investment  advisory fee represented an effective  annual basic rate of 0.36% of
the fund's  average net assets  before an increase of $442,000  (0.09%) based on
performance.

C. The Vanguard Group  furnishes at cost corporate  management,  administrative,
marketing,  and distribution  services. The costs of such services are allocated
to the fund  under  methods  approved  by the  board of  trustees.  The fund has
committed to provide up to 0.40% of its net assets in capital  contributions  to
Vanguard.  At May 31,  2004,  the fund had  contributed  capital of  $166,000 to
Vanguard (included in Other Assets), representing 0.02% of the fund's net assets
and 0.17% of  Vanguard's  capitalization.  The fund's  trustees and officers are
also directors and officers of Vanguard.

                                       21


NOTES TO FINANCIAL STATEMENTS (CONTINUED)

D.  Distributions  are  determined  on a tax  basis  and  may  differ  from  net
investment income and realized capital gains for financial  reporting  purposes.
Differences   may  be  permanent  or  temporary.   Permanent   differences   are
reclassified among capital accounts in the financial statements to reflect their
tax  character.  Temporary  differences  arise  when  certain  items of  income,
expense,  gain,  or loss are  recognized  in  different  periods  for  financial
statement and tax purposes;  these  differences will reverse at some time in the
future.  Differences  in  classification  may also result from the  treatment of
short-term gains as ordinary income for tax purposes.

The fund's tax-basis  capital gains and losses are determined only at the end of
each fiscal year. For tax purposes, at November 30, 2003, the fund had available
realized  losses of  $16,034,000  to offset  future net  capital  gains  through
November 30, 2010.  The fund will use these capital losses to offset net taxable
capital gains, if any, realized during the year ending November 30, 2004; should
the fund  realize net capital  losses for the year,  the losses will be added to
the loss carryforward balance above.

At May 31, 2004, net unrealized  appreciation  of investment  securities for tax
purposes was  $12,183,000,  consisting of  unrealized  gains of  $44,765,000  on
securities  that had risen in value  since their  purchase  and  $32,582,000  in
unrealized losses on securities that had fallen in value since their purchase.

E. During the six months ended May 31, 2004, the fund purchased  $737,419,000 of
investment securities and sold $522,401,000 of investment securities, other than
temporary cash investments.

F. The market value of securities on loan to broker/dealers at May 31, 2004, was
$222,828,000,  for which the fund held cash collateral of $229,766,000. The fund
invests  cash  collateral  received  in  repurchase  agreements,  and  records a
liability for the return of the collateral, during the period the securities are
on loan.

                                       22


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control of your own  investments.  VANGUARD.COM  was built for you--and it keeps
getting better. research and plan your investments with confidence

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     education-- by using our planning tools.
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                                       23



THE PEOPLE WHO GOVERN YOUR FUND

The  trustees of your mutual fund are there to see that the fund is operated and
managed in your best interests since, as a shareholder,  you are a part owner of
the fund.  Your  fund  trustees  also  serve on the  board of  directors  of The
Vanguard  Group,  Inc.,  which is owned by the  Vanguard(R)  funds and  provides
services to them on an at-cost basis.

A majority of Vanguard's board members are  independent,  meaning that they have
no affiliation  with Vanguard or the funds they oversee,  apart from the sizable
personal investments they have made as private individuals.

Our  independent  board members  bring  distinguished  backgrounds  in business,
academia,  and public service to their task of working with Vanguard officers to
establish the policies and oversee the activities of




                     POSITION(S) HELD WITH
NAME                 FUND (NUMBER OF
(YEAR OF BIRTH)      VANGUARD FUNDS
TRUSTEE/OFFICER      OVERSEEN BY
SINCE                TRUSTEE/OFFICER)      PRINCIPAL OCCUPATION(S) DURING THE PAST FIVE YEARS
- ------------------------------------------------------------------------------------------------------------------
                                     
JOHN J. BRENNAN*     Chairman of the       Chairman of the Board, Chief Executive Officer, and Director/Trustee of
(1954)               Board, Chief          The Vanguard Group, Inc., and of each of the investment companies
May 1987             Executive Officer,    served by The Vanguard Group.
                     and Trustee
                     (129)
- ------------------------------------------------------------------------------------------------------------------
INDEPENDENT          TRUSTEES
CHARLES D. ELLIS     Trustee               The Partners of '63 (pro bono ventures in education); Senior Advisor
(1937)               (129)                 to Greenwich Associates (international business strategy consulting);
January 2001                               Successor Trustee of Yale University; Overseer of the Stern School of
                                           Business at New York University; Trustee of the Whitehead Institute
                                           for Biomedical Research.
- ------------------------------------------------------------------------------------------------------------------
RAJIV L. GUPTA       Trustee               Chairman and Chief Executive Officer (since October 1999), Vice
(1945)               (129)                 Chairman (January-September 1999), and Vice President (prior to
December 2001                              September 1999) of Rohm and Haas Co. (chemicals); Director of
                                           Technitrol, Inc. (electronic components), and Agere Systems (commu-
                                           nications components); Board Member of the American Chemistry
                                           Council; Trustee of Drexel University.
- ------------------------------------------------------------------------------------------------------------------
JOANN HEFFERNAN      Trustee               Vice President, Chief Information Officer, and Member of the
HEISEN               (129)                 Executive Committee of Johnson & Johnson (pharmaceuticals/
(1950)                                     consumer products); Director of the University Medical Center at
July 1998                                  Princeton and Women's Research and Education Institute.
- ------------------------------------------------------------------------------------------------------------------
BURTON G. MALKIEL    Trustee               Chemical Bank Chairman's Professor of Economics, Princeton
(1932)               (127)                 University; Director of Vanguard Investment Series plc (Irish invest-
May 1977                                   ment fund) (since November 2001), Vanguard Group (Ireland)
                                           Limited (Irish investment management firm) (since November 2001),
                                           Prudential Insurance Co. of America, BKF Capital (investment
                                           management), The Jeffrey Co. (holding company), and NeuVis, Inc.
                                           (software company).
- ------------------------------------------------------------------------------------------------------------------



the funds.  Among  board  members'  responsibilities  are  selecting  investment
advisors for the funds;  monitoring  fund  operations,  performance,  and costs;
reviewing  contracts;  nominating  and  selecting  new  trustees/directors;  and
electing Vanguard officers.

Each  trustee  serves a fund  until  its  termination;  or until  the  trustee's
retirement,  resignation,  or death;  or  otherwise  as  specified in the fund's
organizational  documents. Any trustee may be removed at a shareholders' meeting
by a vote  representing  two-thirds  of the net asset value of all shares of the
fund  together with shares of other  Vanguard  funds  organized  within the same
trust.  The table on these two pages  shows  information  for each  trustee  and
executive  officer of the fund. The mailing address of the trustees and officers
is P.O. Box 876, Valley Forge, PA 19482.



                      POSITION(S) HELD WITH
NAME                  FUND (NUMBER OF
(YEAR OF BIRTH)       VANGUARD FUNDS
TRUSTEE/OFFICER       OVERSEEN BY
SINCE                 TRUSTEE/OFFICER) PRINCIPAL OCCUPATION(S) DURING THE PAST FIVE YEARS
- ------------------------------------------------------------------------------------------------------------
                                 
ALFRED M. RANKIN, JR. Trustee          Chairman, President, Chief Executive Officer, and Director of NACCO
(1941)                (129)            Industries, Inc. (forklift trucks/housewares/lignite); Director of
January 1993                           Goodrich Corporation (industrial products/aircraft systems and
                                       services); Director of Standard Products Company (supplier for
                                       the automotive industry) until 1998.
- ------------------------------------------------------------------------------------------------------------
J. LAWRENCE WILSON    Trustee          Retired Chairman and Chief Executive Officer of Rohm and Haas Co.
(1936)                (129)            (chemicals); Director of Cummins Inc. (diesel engines), The Mead
April 1985                             Corp. (paper products), and AmerisourceBergen Corp. (pharmaceutical
                                       distribution); Trustee of Vanderbilt University.
- ------------------------------------------------------------------------------------------------------------
EXECUTIVE OFFICERS*

R. GREGORY BARTON     Secretary        Managing Director and General Counsel of The Vanguard Group, Inc.;
(1951)                (129)            Secretary of The Vanguard Group and of each of the investment
June 2001                              companies served by The Vanguard Group.
- ------------------------------------------------------------------------------------------------------------
THOMAS J. HIGGINS     Treasurer        Principal of The Vanguard Group, Inc.; Treasurer of each of the
(1957)                (129)            investment companies served by The Vanguard Group.
July 1998
- ------------------------------------------------------------------------------------------------------------

*Officers  of the funds are  "interested  persons" as defined in the  Investment
Company Act of 1940.

More  information   about  the  trustees  is  in  the  Statement  of  Additional
Information, available from The Vanguard Group.


- ------------------------------------------------------------------------------------------------------------
VANGUARD SENIOR MANAGEMENT TEAM
                                                            
MORTIMER J. BUCKLEY, Information Technology.                   MICHAEL S. MILLER, Planning and Development.
JAMES H. GATELY, Investment Programs and Services.             RALPH K. PACKARD, Finance.
KATHLEEN C. GUBANICH, Human Resources.                         GEORGE U. SAUTER, Chief Investment Officer.
F. WILLIAM MCNABB, III, Client Relationship Group.
- ------------------------------------------------------------------------------------------------------------

JOHN C. BOGLE, Founder; Chairman and Chief Executive Officer, 1974-1996.
- --------------------------------------------------------------------------------



[SHIP]
[THE VANGUARD GROUP(R) LOGO]
Post Office Box 2600
Valley Forge, PA 19482-2600

Vanguard,  The Vanguard Group,  Vanguard.com,  PlainTalk,  and the ship logo are
trademarks of The Vanguard Group, Inc.

All other marks are the exclusive property of their respective owners.

ABOUT OUR COVER

The  photographs  that  appear on the cover of this  report are  copyrighted  by
Michael Kahn.

FOR MORE INFORMATION

This report is intended for the fund's  shareholders.  It may not be distributed
to  prospective  investors  unless it is preceded or  accompanied by the current
fund prospectus.

To  receive  a free  copy  of the  prospectus  or the  Statement  of  Additional
Information,  or to  request  additional  information  about  the  fund or other
Vanguard funds, please contact us at one of the adjacent telephone numbers or by
e-mail through VANGUARD.COM. Prospectuses may also be viewed online.

You can obtain a free copy of Vanguard's proxy voting guidelines by visiting our
website,  www.vanguard.com,  and searching for "proxy voting  guidelines," or by
calling  1-800-662-2739.  They  are  also  available  from  the  SEC's  website,
www.sec.gov.

All  comparative  mutual fund data are from Lipper  Inc. or  Morningstar,  Inc.,
unless otherwise noted.

WORLD WIDE WEB
www.vanguard.com

FUND INFORMATION
1-800-662-7447

DIRECT INVESTOR
ACCOUNT SERVICES
1-800-662-2739

INSTITUTIONAL INVESTOR
SERVICES
1-800-523-1036

TEXT TELEPHONE
1-800-952-3335

(C) 2004 THE VANGUARD GROUP, INC.
ALL RIGHTS RESERVED.
VANGUARD MARKETING
CORPORATION, DISTRIBUTOR.

Q822 072004

Item 2: Not applicable.

Item 3: Not applicable.

Item 4: Not applicable.

Item 5: Not applicable.

Item 6: Not applicable.

Item 7: Not applicable.

Item 8: Not applicable.

Item 9: Not applicable.

Item 10: Controls and Procedures.

     (a)  Disclosure  Controls  and  Procedures.  The  Principal  Executive  and
Financial  Officers  concluded  that the  Registrant's  Disclosure  Controls and
Procedures are effective  based on their  evaluation of the Disclosure  Controls
and Procedures as of a date within 90 days of the filing date of this report.

     (b) Internal  Controls.  There were no significant  changes in Registrant's
internal  controls or in other  factors  that could  significantly  affect these
controls  subsequent to the date of their  evaluation,  including any corrective
actions with regard to significant deficiencies and material weaknesses.

Item 11: Exhibits.
        (a) Certifications.

Pursuant to the  requirements  of the  Securities  Exchange  Act of 1934 and the
Investment Company Act of 1940, the registrant has duly caused this report to be
signed on its behalf by the undersigned, thereunto duly authorized.

       VANGUARD CONVERTIBLE SECURITIES FUND

BY:             (signature)
   ----------------------------------------
                (HEIDI STAM)
              JOHN J. BRENNAN*
          CHIEF EXECUTIVE OFFICER

Date:  July 23, 2004

Pursuant to the  requirements  of the  Securities  Exchange  Act of 1934 and the
Investment  Company  Act of  1940,  this  report  has been  signed  below by the
following  persons on behalf of the  registrant and in the capacities and on the
dates indicated.

       VANGUARD CONVERTIBLE SECURITIES FUND

BY:             (signature)
   ----------------------------------------
                (HEIDI STAM)
              JOHN J. BRENNAN*
          CHIEF EXECUTIVE OFFICER

Date:  July 23, 2004

       VANGUARD CONVERTIBLE SECURITIES FUND

BY:             (signature)
   ----------------------------------------
                (HEIDI STAM)
              THOMAS J. HIGGINS*
                TREASURER

Date:  July 23, 2004

*By Power of  Attorney.  See File Number  2-57689,  filed on December  26, 2002.
Incorporated by Reference.