<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000898031
<NAME> LORD ABBETT SECURITIES TRUST
<SERIES>
<NUMBER> 021
<NAME> INTERNATIONAL SERIES CLASS A
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> OCT-31-2000
<PERIOD-END> APR-30-2000
<INVESTMENTS-AT-COST> 249,687,492
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<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 248,023,516
<SHARES-COMMON-STOCK> 9,032,028
<SHARES-COMMON-PRIOR> 7,565,247
<ACCUMULATED-NII-CURRENT> (1,086,876)
<OVERDISTRIBUTION-NII> 0
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<OVERDISTRIBUTION-GAINS> 0
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<OTHER-INCOME> 0
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<NET-INVESTMENT-INCOME> (928,579)
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<APPREC-INCREASE-CURRENT> 31,634,506
<NET-CHANGE-FROM-OPS> 35,085,093
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (478,220)
<DISTRIBUTIONS-OF-GAINS> (6,142,057)
<DISTRIBUTIONS-OTHER> 0
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<NUMBER-OF-SHARES-REDEEMED> (2,473,419)
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<NET-CHANGE-IN-ASSETS> 70,113,684
<ACCUMULATED-NII-PRIOR> 801,470
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<PER-SHARE-NII> (0.06)
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<PER-SHARE-DIVIDEND> (0.06)
<PER-SHARE-DISTRIBUTIONS> (0.82)
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<EXPENSE-RATIO> 0.83
</TABLE>
