As we develop and our organs form, cells differentiate from one state to another in a coordinated fashion to arrive at a functional organism. How a cell or group of cells determines when and to what new form to adopt in order to create a new tissue or organ is a central question in developmental biology. Understanding how the processes regulating the cell decisions that lead to normal organ development can, and do, inform attempts to guide isolated stem cells in culture toward the same conclusion. It also illuminates developmental mechanisms that are reused during repair and regeneration of tissues and organs. Research in the laboratory focuses on the molecular events of kidney development and repair using the mouse model system. We believe a deeper understanding of the biology driving these processes will help us design new approaches to treat human diseases of the kidney. We pose two questions for ourselves: 1) what are the molecular components that guide the formation of new nephrons from kidney progenitors cells, and 2) what molecular pathways are active during the repair process after acute kidney injury? Answers to the first question will aid in designing a regenerative medicine approach, which is to use nephron progenitors to treat failing kidneys by inducing new nephron formation. To accomplish this we need to understand how nephron development occurs during organogenesis so that we may encourage the same events in adult diseased kidneys and molecularly monitor the results. The second question is designed to identify potential therapeutic targets, such as signaling pathways, to promote kidney repair after organ transplantation. We view both these questions in the context of regenerative medicine. That is, to learn how to coax progenitor cells into new functional nephrons to treat failing kidneys, or enhance the recovery of surviving cells after an injury.