This article reviews the use of exercise as a therapeutic and adjunctive interven- ion in the prevention of weight gain, obesity, and metabolic consequences in multiple populations with psychiatric illnesses. The purpose was to identify he current state of the science for the use of exercise as a psychiatric nursing intervention, as well as the gaps and methodological issues in current studies. To do this, research and review articles published between 1998 and 2010 were reviewed. It was found that psychiatric nurses are taking the first steps n incorporating exercise into their recommendations and interventions in populations with psychiatric illnesses, but a long jouriney remains to make a significant difference in clients' lives.