This chapter begins by reviewing the Darwinian account of biological innovation, which is based on what Ernst Mayr calls "population thinking" and posits two kinds of key mechanisms underlying the innovation process, variation and selection. The chapter then argues that the increasingly popular tendency to adapt this account to provide the foundations for a theory of human sociocultural innovation is ill-advised. Human sociocultural organizations are self-reflexive and self-modifying, through negotiation processes that can lead to transformations in organizational structure and functionality, including the essential activities of recruitment, differentiation and coordination. Innovation in these organizations is accomplished through processes of organizational transformation, and to understand how these work, "organization thinking" rather than "population thinking" is required. The fundamental questions that organization thinking addresses include the following: What is social organization? How are particular social organizations constructed, maintained, and transformed? What kinds of functionality do social organizations support, and how do they create new functionality? In addressing these questions, the chapter describes a bootstrapping dynamic, whereby organizations generate new functionality, which is instantiated in activities that in turn generate new organizations.