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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 officers 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 officers and I have disclosed, based
         on our most recent evaluation, to the Registrant's auditors and the
         audit committee or 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 data; and

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

     6.  The Registrant's other certifying officers and I have indicated in this
         report whether or not there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.

Date: June 21, 2004


                                                     /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 officers 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 officers and I have disclosed, based
         on our most recent evaluation, to the Registrant's auditors and the
         audit committee or 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 data; and

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

     6.  The Registrant's other certifying officers and I have indicated in this
         report whether or not there were significant changes in internal
         controls or in other factors that could significantly affect internal
         controls subsequent to the date of our most recent evaluation,
         including any corrective actions with regard to significant
         deficiencies and material weaknesses.


Date: June 21, 2004


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