FOREIGN LANGUAGE PROFICIENCY TESTS OF THE MODERN LANGUAGE ASSOCATION WERE USED TO DETERMINE THE DEGREE OF IMPROVEMENT ACHIEVED BY 2,300 FOREIGN LANGUAGE TEACHERS WHO RECEIVED ADVANCED TRAINING IN THE 1966 NDEA SUMMER FOREIGN LANGUAGE INSTITUTES. TEACHERS OF FRENCH, GERMAN, ITALIAN, RUSSIAN, AND SPANISH IN 52 INSTITUTES WERE TESTED AT THE BEGINNING AND THE END OF THE INSTITUTES IN THE SEVEN FIELDS IN WHICH INSTRUCTION WAS OFFERED--LISTENING COMPREHENSION, SPEAKING, READING, WRITING, APPLIED LINGUISTICS, CIVILIZATION AND CULTURE, AND PROFESSIONAL PREPARATION. THOUGH THERE WAS CONSIDERABLE VARIATION IN THE AMOUNT OF GAIN ATTAINED BY THE TEACHERS ON THE SEVEN TESTS, A COMPARISON OF GAINS AMONG INSTITUTES SHOWED THAT, IN GENERAL, THE NONSKILL AREAS AND WRITING AND SPEAKING HAD RECEIVED THE GREATEST AMOUNT OF EMPHASIS IN THE INSTITUTES. READING AND LISTENING COMPREHENSION WERE LEAST EMPHASIZED. TWO LIMITATIONS ON THE DATA WERE THE LACK OF A CONTROL GROUP AND THE POSSIBLE LOW DEGREE OF COMPARABILITY OF SCORES FOR ALTERNATE FORMS OF EACH TEST. GAINS BY LANGUAGE AND INSTITUTES ARE PRESENTED IN STATISTICAL TABLES. (AM)