DATRON SYSTEMS INCORPORATED
                             3030 ENTERPRISE COURT
                            VISTA, CALIFORNIA 92083

                                  July 9, 2001

Dear Datron Stockholders:

    I am pleased to inform you that on June 24, 2001, Datron Systems
Incorporated entered into an Agreement and Plan of Merger and Reorganization
with The Titan Corporation pursuant to which a subsidiary of Titan has today
commenced an offer to acquire all of the outstanding shares of Datron common
stock through a two-step transaction, including an exchange offer and a
subsequent merger.

    In the exchange offer, Datron stockholders will receive a fraction of a
share of Titan common stock for each share of Datron common stock held. The
exchange ratio determining the number of shares of Titan common stock you will
receive is based on the average closing price of Titan common stock with
adjustments if the price of Titan common stock rises above or falls below
certain levels. For a complete description of the exchange ratio, including
examples, please refer to Titan's Prospectus, which is enclosed with this
letter, under the headings "The Transaction--The Exchange Ratio" and "The
Transaction--Illustrative Table of Exchange Ratios and Value of Offer/Merger
Consideration."

    The exchange offer is subject to, among other things, the tender of at least
a majority of the outstanding shares of Datron common stock prior to the
expiration of the exchange offer.

    Following the completion of the exchange offer, the acquisition of any
remaining shares of Datron common stock will be completed through a merger of
Datron with a wholly owned subsidiary of Titan in which each share of Datron
common stock not exchanged in the offer will be converted into shares of Titan
common stock at the same exchange ratio as used in the offer.

    After careful consideration, your Board of Directors has unanimously
approved the merger agreement and determined that the merger agreement and the
transactions contemplated thereby, including the exchange offer and the merger,
are advisable and fair to and in the best interests of Datron and its
stockholders, and unanimously recommends that Datron stockholders accept the
exchange offer.

    I and the other directors and executive officers of Datron have individually
agreed to exchange our Datron shares pursuant to the offer. These shares, in
total, represent approximately 3.0% of the outstanding shares of common stock of
Datron.

    You are receiving, in this envelope, a copy of Datron's Schedule 14D-9
containing the Datron board's recommendation and explaining the reasons behind
it, as well as the background to the transaction and other important
information. Included as Annex C to Titan's Prospectus is the written opinion,
dated June, 22, 2001 of Philpott, Ball & Werner, Datron's financial advisor, to
the effect that, as of the date of the opinion, the consideration to be paid
pursuant to the merger agreement is fair, from a financial point of view, to
Datron's stockholders. I urge you to read the opinion carefully and in its
entirety.

    You are also receiving, in this envelope, Titan's Prospectus which provides
detailed information concerning Titan, the exchange offer and the merger and
Titan's Letter of Transmittal and related items to be used for tendering your
shares. These documents have also been filed with the Securities and Exchange
Commission. I again urge you to read the enclosures carefully.

    The exchange offer and withdrawal rights will expire at 12:00 midnight, New
York City time, on Friday, August 3, 2001, unless extended. If you want to
participate in the exchange offer, you will need to properly tender your shares
prior to the expiration date and time. Information on how to properly tender
your shares is included in the Prospectus and the Letter of Transmittal, and you
may call the Information Agent, D.F. King & Co., Inc. at (800) 628-8510 if you
have any questions.

                                          Sincerely,

                                          /s/ David A. Derby
                                          David A. Derby
                                          Chairman, President and Chief
                                          Executive Officer