It is generally acknowledged that, beginning in the 1960s and continuing to the present day, evolutionary biology has been significantly transformed by the incorporation of ideas and techniques from molecular biology. In this seminar, participants reflected on these four decades of change. How, exactly, have the general theories and central questions of evolutionary biology changed as a result of molecular considerations? How, exactly, have the standards and practices of evolutionary biology been affected? And, reciprocally, how has evolutionary biology influenced molecular biology? In the process of pursuing these overarching questions, we considered particular issues and episodes having to do with rates and mechanisms of evolutionary change, the evolution of the genome, molecular phylogenetics, approaches to modeling, and the development of tests to discriminate between alternative hypotheses.