Physical activity exerts beneficial effects on glucose homeostasis that are channeled through our genes. Where variation in the target genes of physical activity exists, gene-physical activity interactions may occur, such that individual genetic profiles inflict differing physiological responses to an equal bout of physical activity. Individuals with specific genetic profiles are also expected to be more responsive to the beneficial effects of physical activity in the prevention of type 2 diabetes. Identification of such gene-physical activity interactions could give new insights into the biological mechanisms of how type 2 diabetes develops, which could open up new avenues for the development of novel treatments. It has also been postulated that knowledge of interactions could improve the prevention and treatment of type 2 diabetes by enabling targeted interventions. The present chapter will introduce the reader to the recent advances in the genetics of type 2 diabetes, summarize the current evidence on gene-physical activity interactions in relation to type 2 diabetes, and outline how information on gene-physical activity interactions might help improve the prevention and treatment of type 2 diabetes. Finally, we will discuss the existing and emerging strategies that might enhance our ability to identify and exploit gene-physical activity interactions in the etiology of type 2 diabetes. © 2014 S. Karger AG, Basel.