THIS PAPER APPROACHES THE EFFECTS OF PATTERS OF SPECIALIZATION ON BRAZILIAN FOREIGN TRADE. BY APPLYIGN A CONSTANT-MARKET-SHARE ANALYSIS TO THE BRAZILIAN EXPORT AND IMPORT BILLS BETWEEN EARLY-80S AND MID-90S, WE ATTEMPT TO ASSESS THE QUANTITATIVE WEIGHTS OF STRUCTURAL EFFECTS, ALLOCATION EFFECTS AND COMPETITIVENESS EFFECTS ALONG THAT PERIOD. OUR RESULTS POINT OUT TO A SUBSTANTIAL NEGATIVE ROLE PLAYED BY PREVAILING PATTERNS OF SPECIALIZATION WITH RESPECT TO THE ATTAINMENT OF TRADE BALANCES COMPATIBLE WITH DOMESTIC HIGH GROWTH.THIS PAPER APPROACHES THE EFFECTS OF PATTERS OF SPECIALIZATION ON BRAZILIAN FOREIGN TRADE. BY APPLYIGN A CONSTANT-MARKET-SHARE ANALYSIS TO THE BRAZILIAN EXPORT AND IMPORT BILLS BETWEEN EARLY-80S AND MID-90S, WE ATTEMPT TO ASSESS THE QUANTITATIVE WEIGHTS OF STRUCTURAL EFFECTS, ALLOCATION EFFECTS AND COMPETITIVENESS EFFECTS ALONG THAT PERIOD. OUR RESULTS POINT OUT TO A SUBSTANTIAL NEGATIVE ROLE PLAYED BY PREVAILING PATTERNS OF SPECIALIZATION WITH RESPECT TO THE ATTAINMENT OF TRADE BALANCES COMPATIBLE WITH DOMESTIC HIGH GROWTH.