Individuals who face significant adversity are typically able to resume normal functioning despite this hardship. Resilience is a dynamic process at any level of functioning that encompasses the capacity by which these individuals adapt positively following adversity. Resilience science aims to elucidate the mechanisms of successful adaption following adverse situations, allowing researchers to better understand why some individuals adapt better than others. In the present chapter we synthesize literature on biologic systems and their resilient functioning, including neurobiologic, hormonal, and genetic aspects of resilience. Utilizing a developmental psychopathology approach, we emphasize the importance of taking an integrative, multiple systems perspective when examining resilient functioning by incorporating biologic and psychosocial systems and the necessity for collaboration among researchers from a variety of disciplines. Finally, we discuss the application of resilience science and how these results can be integrated into intervention efforts aimed to promote resilient functioning in individuals.