Athletes in a multitude of sports (e.g., cricket, cycling, marathon running, swimming, tennis) have been observed talking to themselves during training and competition. To understand self-talk, sport psychology researchers have created and validated a myriad of self-talk questionnaires assessing self-talk use, content, and function. Studies exploring self-talk in sport and the effects of self-talk on sport performance have been conducted, primarily by categorizing recollected self-talk, exploring the effects of particular types of self-talk, and evaluating the effects of self-talk interventions. Recently, greater attention has been paid to the theoretical underpinnings of self-talk in sport contexts. Borrowing from the dual process theory approach of Kahneman (2011), the sport-specific model of self-talk (Van Raalte, Vincent, & Brewer, 2017) was developed to address key questions about self-talk and provide a theoretical context that could be used to integrate and identify areas for future research. This presentation will include an overview of research on self-talk in sport, examination of theoretical factors that can potentially advance understanding of athletes’ inner experiences, and the dynamic interplay between System 2 (intentionally-used) self-talk and System 1 (spontaneously-expressed and impression-focused) self-talk in sport. The presentation will conclude with a discussion of theoretically-based, practical self-talk tips that can guide work with coaches, teams, and athletes.