This study was undertaken to develop guidelines for making interpretive inferences from scores on the Test of English for International Communication (TOEIC), a norm-referenced test of English-language listening comprehension (LC) and reading (R) skills, about level of ability to use English in face-to-face conversation, indexed by performance in the language proficiency interview (LPI) situation. LPI performance, rated according to behaviorally defined levels on the LPI/ILR/FSI quasi-absolute proficiency scale, was treated as a context-independent criterion, using the familiar regression model in an apparently novel application (for such criterion-referencing purposes) in the context of a large-scale ESL-testing program. The study employed TOEIC/LPI data-sets generated during operational ESL assessments in representative TOEIC-use settings (places of work or work-related ESL training) in Japan, France, Mexico, and Saudia Arabia, involving samples of adult, educated ESL users/learners in or preparing for ESL-essential positions with companies engaged in international commerce. The pattern of TOEIC/LPI concurrent correlations was consistent across samples and there was relatively close fit between sample LPI means and estimates from TOEIC scores, especially TOEIC-LC, using combined sample regression equations. Theoretical and pragmatic implications of the findings are discussed. General guidelines are provided for making inferences about LPI-assessed level of oral English proficiency from TOEIC scores. Directions are suggested for further research and development activities in the TOEIC testing context.