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                                                                 Exhibit 99.cert

                                 CERTIFICATIONS

                         Pursuant to Section 302 of the
                           Sarbanes-Oxley Act of 2002

I, Robert S. Dow, certify that:

    1.  I have reviewed this report on Form N-CSR of Lord Abbett Securities
        Trust;

    2.  Based on my knowledge, this report does not contain any untrue
        statements of material fact or omit to state a material fact necessary
        to make the statements made, in light of the circumstances under which
        such statements were made, not misleading with respect to the period
        covered by this report;

    3.  Based on my knowledge, the financial statements, and other financial
        information included in this report, fairly present in all material
        respects the financial condition, results of operations, changes in net
        assets, and cash flows (if the financial statements are required to
        include a statement of cash flows) of the Registrant as of, and for, the
        periods presented in this report;

    4.  The Registrant's other certifying officer and I are responsible for
        establishing and maintaining disclosure controls and procedures (as
        defined in Rule 30a-3(c) under the Investment Company Act of 1940) for
        the Registrant and have:

            a)  designed such disclosure controls and procedures, or caused such
                disclosure controls and procedures to be designed under our
                supervision, to ensure that material information relating to the
                Registrant, including its consolidated subsidiaries, is made
                known to us by others within those entities, particularly during
                the period in which this report is being prepared; and

            b)  evaluated the effectiveness of the Registrant's disclosure
                controls and procedures and presented in this report our
                conclusions about the effectiveness of the disclosure controls
                and procedures, as of a date within 90 days prior to the filing
                date of this report based on such evaluation;

    5.  The Registrant's other certifying officer and I have disclosed to the
        Registrant's auditors and the audit committee of the Registrant's board
        of trustees (or persons performing the equivalent functions):

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            a)  all significant deficiencies and material weaknesses in the
                design or operation of internal control over financial reporting
                which are reasonably likely to adversely affect the Registrant's
                ability to record, process, summarize, and report financial
                information; and

            b)  any fraud, whether or not material, that involves management or
                other employees who have a significant role in the Registrant's
                internal control over financial reporting.


Date: December 22, 2003
      -----------------


                                      /s/ ROBERT S. DOW
                                      -----------------
                                      Robert S. Dow
                                      Chief Executive Officer,
                                      Chairman and President

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                                 CERTIFICATIONS

                         Pursuant to Section 302 of the
                           Sarbanes-Oxley Act of 2002

I, Joan A. Binstock, certify that:

    1.  I have reviewed this report on Form N-CSR of Lord Abbett Securities
        Trust;

    2.  Based on my knowledge, this report does not contain any untrue
        statements of material fact or omit to state a material fact necessary
        to make the statements made, in light of the circumstances under which
        such statements were made, not misleading with respect to the period
        covered by this report;

    3.  Based on my knowledge, the financial statements, and other financial
        information included in this report, fairly present in all material
        respects the financial condition, results of operations, changes in net
        assets, and cash flows (if the financial statements are required to
        include a statement of cash flows) of the Registrant as of, and for, the
        periods presented in this report;

    4.  The Registrant's other certifying officer and I are responsible for
        establishing and maintaining disclosure controls and procedures (as
        defined in Rule 30a-3(c) under the Investment Company Act of 1940) for
        the Registrant and have:

            a.  designed such disclosure controls and procedures, or caused such
                disclosure controls and procedures to be designed under our
                supervision, to ensure that material information relating to the
                Registrant, including its consolidated subsidiaries, is made
                known to us by others within those entities, particularly during
                the period in which this report is being prepared; and

            b.  evaluated the effectiveness of the Registrant's disclosure
                controls and procedures and presented in this report our
                conclusions about the effectiveness of the disclosure controls
                and procedures, as of a date within 90 days prior to the filing
                date of this report based on such evaluation;

    5.  The Registrant's other certifying officer and I have disclosed to the
        Registrant's auditors and the audit committee of the Registrant's board
        of trustees (or persons performing the equivalent functions):

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            a.  all significant deficiencies and material weaknesses in the
                design or operation of internal control over financial reporting
                which are reasonably likely to adversely affect the Registrant's
                ability to record, process, summarize, and report financial
                information; and

            b.  any fraud, whether or not material, that involves management or
                other employees who have a significant role in the Registrant's
                internal control over financial reporting.


Date: December 22, 2003
      -----------------


                                      /s/ JOAN A. BINSTOCK
                                      --------------------
                                      Joan A. Binstock
                                      Chief Financial Officer and Vice President