This chapter is dedicated to volunteering in environmental protection, with its ecological, societal, and individual significance. Initially, current figures on the extent of volunteering are presented, along with a classification into different forms, and the most important defining characteristics are elaborated. Subsequently, the motivation for this volunteering is considered. General explanatory models for volunteering are cited, and the motivational peculiarities of volunteering in environmental protection are highlighted. Then, the question of how this volunteering can be successfully designed is answered. In addition to responsibility and justice-related variables, the motives of the (potential) volunteers as well as activity and organizational characteristics should be considered. Finally, an outlook on current developments is provided.