This systematic review assesses the state of the literature regarding the impacts of outdoor education instructors' behaviors and traits on participant outcomes. Twenty-seven articles are reviewed in detail, and student outcomes in relation to instructor behaviors and traits and to programmatic elements are identified. A range of participant outcomes including social and emotional skills development, group cohesion, and identity development are discussed. Twelve distinct outdoor education instructor behaviors are identified, and the five most salient are discussed. Instructor traits such as interpersonal qualities are emphasized. Programmatic elements employed by instructors that impact participant outcomes include (1) incorporating elements of experiential learning, (2) debriefing and feedback, and (3) participant reflection. Suggestions for future research are provided including conducting quasi-experimental studies that segment groups based on instructor behaviors, traits, and leadership theories; work that identifies participant and instructor demographics; and scholarship using diverse methodological approaches.