While prior research has recognized the importance of balancing between exploitation and exploration, there have been few studies that examine exploration and exploitation at the individual and group levels of analyses. In this study, we examine how innovators gain breadth and depth of expertise, and the role that specialization versus diversity of expertise plays in cultivating a successful innovator. We conduct a case study of innovation behavior of research scientists in 3M, which was ranked 3rd and 7th in the Business Week’s Most Innovative companies in 2006 and 2007 respectively. In addition, we examine how the organization’s innovation culture affects scientists’ innovation behavior, and how the innovation culture is sustained in the organization.