Steroidogenic factor 1 (SF-1) gene, identified by Keith Parker in 1992, encodes for an orphan nuclear receptor, NR5A1, whose expression is detected during fetal life in adrenal and gonadal steroidogenic tissues, but also in the developing hypothalamus and in pituitary gonadotropic cells. SF-1 knock-out mouse models exhibit complete adrenal and gonadal agenesis. Human mutations of this transcription factor, were initially associated with primary adrenal failure and male gonadal dysgenesis with various degrees of under androgenization. More recently, identification of novel SF-1 mutations responsible for isolated 46, XY gonadal dysgenesis or 46, XX primary ovarian insufficiency, underscores its central role in the control and maintenance of adrenal and reproductive functions. A better understanding in the regulatory mechanisms of SF-1 signaling pathway, will open new avenues for diagnostic and therapeutic managements of sex differentiation disorders and infertilities.