Broadly conceptualized as the energy for action, the construct of motivation drives human behavior. Motivation is, therefore, of utmost concern in fields where individuals occupy roles that involve facilitating the actions of others. Physical education is one such field, as teacher-educators attempt to mold the behaviors of preservice teachers and inservice teachers attempt to mold the behaviors of their students. Self-determination theory is one theory of human motivation that has been widely recruited to study the construct within the context of school-based physical education. This theory holds that motivation potentially assumes multiple forms, ranging from that which is completely extrinsic, through those that are increasingly internalized, to motivation that is completely autonomous or self-determined. Motivation is autonomous in nature insofar as the psychological needs for autonomy, competence, and relatedness are satisfied. With respect to physical education, a sequence has been postulated whereby teachers’ psychological need satisfaction leads to more autonomous forms of motivation for teaching, facilitating the provision of more need-supportive forms of instruction, leading to more autonomous student motivation, in turn offering many desirable in-class and leisure time student outcomes. This dissertation examined various aspects of this motivational sequence. In study one, a structural equation model generated from survey data completed by inservice physical education teachers (N = 477) revealed perceived mattering and role stress as two antecedents to physical education teachers’ psychological need satisfaction. Teachers’ perceived mattering predicted perceptions of autonomy, competence, and relatedness satisfaction directly as well as indirectly by attenuating perceptions of role stress. Considerable research has documented the benefits to teachers and students alike as a result of teachers’ utilization of more need-supportive motivating styles. These motivating styles have been linked to causality orientations, which are believed to be socially developed. Therefore, drawing jointly from self-determination and occupational socialization theories, the second study sought to examine the development of physical education teachers’ motivating styles over the course of their lives. Participants were purposefully selected from the sample of teachers involved in study one (N = 29). Data collected from semi-structured interviews indicated that teachers’ motivating styles were influenced by the nature of the contexts in which they enjoyed psychological need satisfaction during their acculturation and professional socialization, their professional identity, and the extent to which they perceived experiencing psychological need satisfaction at work. Study three was an intervention study involving one preservice teacher, Jason, and the students in his fifth grade class (N = 58). The intervention sought to increase Jason’s provision of need-supportive instruction within Sport Education and examine any accompanying change in student learning. Jason taught one season of floor hockey, during which his need-supportive teaching behaviors were quantified. Additionally, the students were administered cognitive (pre, post, retention) and contextualized and decontextualized skill (pre, post) assessments. Following a workshop grounded in self-determination theory on need-supportive instruction, Jason then taught a season of pickleball to the same students. Data collection procedures during the pickleball season mirrored those used during the floor hockey season. Findings revealed the success of the intervention. Additionally, cognitive learning appeared to take place on a deeper level as indicated by increased test scores at the retention time point. Finally, though significant improvements in contextualized skill performance were observed during both seasons, the extent of the improvement was significant more post-intervention. Significant improvements in decontextualized skill performance occurred pre- and post-intervention.