This study considers the benefits of coteaching in the context of the outdoors. It explores the use of coteaching in a professional development program and investigates all the cited outcome categories for teachers: cognitive, affective, coteaching, and professional development. Coteaching pairs coplanned, cotaught, and coevaluated "Shared Learning Days" in the outdoors. Eight teachers took part with 180 students in their last year of elementary school or their first year of (junior) high school. This article demonstrates how a model of professional development, with coteaching at its core, is beneficial for the development of teachers who are teaching "outside" their comfort zone (outdoors) and expected to focus on skills-based teaching and learning. In particular, the benefits of attitudinal change among the teachers involved is discussed.