SUMMARY: This study examines the relationship between TOEIC Listening and Reading scores and TOEIC Speaking and Writing scores in order to determine whether or not Listening and Reading scores should be used as predictors of Speaking and Writing scores and vice versa. Findings support the validity of test scores for the measured skills (e.g., Listening and Reading test scores provide meaningful interpretations of Listening and Reading skills). The findings also suggest that the skills all assess different abilities, and researchers concluded that predictions of speaking and writing scores based on reading and listening were relatively imprecise. This research supports the argument that four-skill testing provides the most accurate picture of a test taker's language proficiency. ABSTRACT: The purpose of this study was to examine the correlations of scores among the TOEIC Listening and Reading test and the TOEIC Speaking and Writing tests to determine whether the tests measure four separate language skills. This paper is part of the Research Foundation for TOEIC: A Compendium of Studies, published by ETS in 2010.