What factors in individualized tutoring sessions impact university students' self-efficacy for mastering a foreign language (FL)? For 29 initial sessions (Italian, Spanish, French, or Portuguese) at a university tutoring program, tutees completed pretutoring and posttutoring questionnaires indicating their self-efficacy for learning the FL. Transcripts of the 4 sessions with the greatest increases and the 4 with greatest decreases in self-efficacy were analyzed and compared for features, including session length, amount of overlapped speech, ratio of tutor/tutee talk, language choice, questioning, rules, examples, statements about the FL, admissions of error and of lack of knowledge by the tutor, and attributional statements. Motivationally effective tutoring sessions tended to be shorter, to focus on deeper understanding of the FL structure through explanation of rules and deep-level questioning, and to characterize and model the FL as learnable and regular.