Steroidogenic factor-1 (SF-1) (NR5A1) is a member of the nuclear receptor superfamily that is expressed widely throughout the adrenal and reproductive axes during development and plays a central role in the function of these endocrine systems in post-natal and adult life. Much has been learned about the role of this transcription factor since its initial cloning in 1992, largely due to the creation of an Sf-1 (FtzF1) knockout mouse model, in vitro studies of nuclear receptor function and, more recently, following identification and characterization of patients with naturally-occurring SF-1 mutations. In this review, we will summarize how our knowledge of SF-1 in endocrine development and disease evolved to its current state, focusing on the spectrum of phenotypes associated with mutations in this transcription factor in patients who might present to a pediatric endocrinologist.