Behavioral genetics approaches to the study of individual differences have been widely applied in various disciplines in social sciences to investigate the “nature versus/and nurture” issue through disentangling influences from genetic factors (i.e., influences from nature) and environmental factors (i.e., influences from nurture). However, leadership research has only recently embraced such approaches. This is unfortunate considering the long-standing debate on whether leaders are born or made, and the more recent emphasis on person–environment interplay in leadership research. In this chapter, the authors first discuss the importance of the behavioral genetics approach to organizational research. They then introduce two types of behavioral genetics research that have been adopted so far: classic twin studies and molecular genetic research capitalizing on specific DNA information. Specifically, they explain how univariate biometric analyses, and bivariate biometric analyses based on twin studies can be applied to study important issues in leadership research. With respect to molecular genetic research, they discuss the candidate gene approach and genome-wide association studies, and how they can be useful in advancing leadership research. They also provide brief research examples based on previous research in which such approaches can be employed in addressing critical questions in leadership.