This article investigates results and antecedents of willingness to communicate WTC in a second language L2 through 2 separate investigations conducted with Japanese adolescent learners of English. In the first investigation, involving 160 students, a model was created based on the hypothesis that WTC results in more frequent communication in the L2 and that the attitudinal construct international posture leads to WTC and communication behavior. This model was tested with structural equation modeling and was found to fit the data well. The second investigation with 60 students who participated in a study-abroad program in the United States confirmed the results of the first. Finally, frequency of communication was shown to correlate with satisfaction in interpersonal relationships during the sojourn.