SUPPLEMENT TO THE CURRENTLY EFFECTIVE PROSPECTUSES:

                                -----------------

                             DWS MONEY MARKET SERIES

                             Premium Class S Shares

                          Prime Reserve Class S Shares

The following information supplements the disclosure in the "Other Policies and
Risks" section of the fund's prospectus:

The fund may also post on the Web site, on a more frequent basis, a percentage
breakdown of the holdings of the fund by type of security.

The following information replaces similar disclosure in the "Policies You
Should Know About -- Policies about transactions" section of the fund's
prospectus:

Transaction Processing. Orders for the purchase of shares by wire transfer will
normally be effective at the share price next computed after receipt of the wire
transfer of the amount to be invested. If a wire transfer purchase order is
received in good form prior to 5:00 p.m. Eastern time, it will normally receive
the dividend for that day.

Investments by check will be effective on the business day following receipt and
will earn dividends the following business day.

Orders processed through dealers or other financial services firms via Fund/SERV
will be effected at the share price calculated on the trade day (normally the
date the order is received). Purchases processed via Fund/SERV will begin
earning dividends on the day a fund receives the payment (typically the next
business day). For redemptions processed via Fund/SERV, you generally will
receive dividends accrued up to, but not including, the business day that
payment for your shares are made.


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                                                                     [Logo]DWS
                                                                       SCUDDER
                                                           Deutsche Bank Group

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When selling shares, shareholders generally receive dividends up to, but not
including, the business day following the day on which the shares were sold. If
the fund receives a sell request before 5:00 p.m. Eastern time and the request
calls for proceeds to be sent out by wire, the proceeds will normally be wired
on the same day. However, the shares sold will not earn that day's dividend.

As noted elsewhere in the prospectus, proceeds of a redemption may be delayed.
The ability to receive "same day" wire redemption proceeds can be affected by a
variety of circumstances including the time that the request is made, the level
of redemption requests and purchase orders and general market conditions.
Requests for same day wire that are received earlier in the day will be given
priority over requests received later in the day in the event that it is
necessary to limit the amount of same day wire redemptions.

The following information replaces similar disclosure under the "Policies You
Should Know About -- How the fund calculates share price" section of the fund's
prospectus:

The fund is open for business each day the New York Stock Exchange is open.
Normally, the fund calculates its share price once every business day at 5:00
p.m. Eastern time. The close of regular trading on the Exchange is typically
4:00 p.m. Eastern time, but sometimes it is earlier, as in the case of scheduled
half-day trading or unscheduled suspensions of trading. In the event of
scheduled partial day trading or unscheduled suspensions of trading on the
Exchange, the calculation of share price shall be as of the close of trading on
the Exchange and the latest time for receipt of wire purchase transactions
entitled to receive same day dividend treatment and for receipt of redemption
orders for same day wire transfer of proceeds will be the earlier of (a) the
times set forth in the prospectus or (b) the early closing time of the Exchange.
The fund seeks to maintain a stable $1.00 share price.

Except as provided below, purchase, redemption and exchange orders must be
received in good order by 4:00 p.m. Eastern time (or prior to the close of the
fund, if the Exchange closes early on such date) on a business day on which the
fund is open in order to be effective on that day; otherwise such orders will be
effective on the next business day. However, on a normal business day that the
fund/portfolio calculates its share price at 5:00 p.m. Eastern time as provided
above, purchase orders with payment sent by wire and redemption orders with
proceeds to be sent by wire, ACH or check that are communicated by telephone
(but not

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<PAGE>

by the Automated Information Line) and are received in good order by 5:00 p.m.
Eastern time on such business day will be effective on that business day.

The fund may, but is not required to, accept certain types of purchase and
redemption orders (not including exchanges) on days that the Exchange is closed,
or beyond an Exchange early closing time (referred to as a "Limited Trading
Period") if: (a) the Federal Reserve system is open, (b) the primary trading
markets for the fund's portfolio instruments are open and (c) the Advisor
believes there will be adequate liquidity in the short-term markets. During any
such Limited Trading Period, the fund will only accept purchase orders by wire
and telephone redemption orders with proceeds to be sent by wire, ACH or check
and will not accept orders by any other means. (Automated Telephone Line orders
are not permitted.) If redemption proceeds are requested by ACH or check, the
transmission of the ACH payment or the mailing of the check, as the case may be,
will be delayed by at least one business day in comparison to normal trading
periods. Orders submitted by other means will be processed on the next day that
the Exchange is open. The calculation of share price will be at the time set
forth in the prospectus for normal trading days. Orders must be submitted by the
cut-off times for receipt of wire purchases entitled to that day's dividend and
for receipt of telephone redemption orders for same day wire transfer, which
will be the earlier of: (a) the times set forth in the prospectus for normal
trading days or (b) such earlier times that the fund determines based on the
criteria described above. If redemption proceeds are requested by ACH or check,
orders must be received prior to the calculation of share price. Please call
(877) 237-1131 or visit our Web site at www.dws-scudder.com for additional
information about whether the fund will be open for business on a particular
day. Information concerning the intention of a fund to be open for a Limited
Trading Period will be available at least one business day prior to the
applicable day that the Exchange is closed or is closing early in the case of
scheduled closings and as soon as practical in the case of unscheduled closings.


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               Please Retain This Supplement for Future Reference




March 31, 2008
PS309/402-3600

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