THIS ADDRESS, GIVEN AT THE INTERNATIONAL CONFERENCE ON MODERN FOREIGN LANGUAGE TEACHING (BERLIN, SEPTEMBER 1964), PRESENTS A GENERAL DISCUSSION OF THE PRESENT SCOPE, ROLE, AND POTENTIAL USE OF RESEARCH IN FOREIGN LANGUAGE TEACHING METHODOLOGY, AND MAINTAINS THAT THE BEST RESEARCH IS THAT WHICH IS CLOSELY ALLIED WITH THEORY, AND THE HARDEST TO APPLY IS THAT WHICH HAS DIRECT BEARING ON CLASSROOM PROCEDURE. IT POINTS OUT THE GREAT SCOPE FOR DEVELOPMENT IN THE THEORY OF FOREIGN LANGUAGE LEARNING, CITING FAVORABLY THE WORK OF MATHEMATICAL LEARNING THEORISTS WHO HAVE DEVISED EXACT EQUATIONS FOR THE RATE AT WHICH MATERIAL IS LEARNED OR FORGOTTEN. THE NEED OF FORMING AN ACCURATE THEORETICAL COMPARISON BETWEEN THE "AUDIO-LINGUAL HABIT" AND "COGNITIVE CODE-LEARNING" THEORIES IS DISCUSSED, SUCH EXPERIMENTS BEING DIFFICULT TO CONTROL SINCE IT IS ALMOST IMPOSSIBLE TO PREDICT THE EXACT TECHNIQUES A STUDENT WILL EMPLOY, AND SINCE THE THEORETICAL CONTRAST HAS NOT BEEN SUFFICIENTLY WELL-CONCEIVED. NEITHER METHOD IS BASED ON MODERN THEORIES OF THE PSYCHOLOGY OF LANGUAGE LEARNING, AND THE DISCUSSION CONCLUDES WITH A CRITICAL COMPARISON OF THE TWO, RECOMMENDING A JOINING OF AUDIO-LINGUAL TECHNIQUE WITH SOME OF THE BETTER ELEMENTS OF COGNITIVE CODE-LEARNING THEORY. THIS ARTICLE IS A REPRINT FROM THE "MODERN LANGUAGE JOURNAL," VOLUME 49, NUMBER 5, MAY 1965, PAGES 273-281. (RW)