Roles for steroid hormones in regulating neural function are well established. First solved were mechanisms for simple sex behaviors. New frontiers include steroid hormone effects on generalized brain arousal, including direct hormonal effects on the biological clock, the suprachiasmatic nucleus. With effects ranging from the sculpting of the nervous system early in development, to the modulation of the CNS in adulthood, steroid hormones have diverse and important roles in both physiology and behavior. While the “classic” genomic actions of the gonadal hormones are well understood, non-genomic mechanisms of steroid hormone action are only now being fully realized. This review will focus on  (1) the recent findings surrounding the non-genomic actions of androgens, estrogens, and glucocorticoids, emphasizing that they are likely to have evolved to synergize with genomic effects; (2) the ever-increasing understanding of the role of steroid receptor cofactors in the regulation of gene transcription; and (3) the similarities and differences between different DNA steroid response elements, and what such characteristics mean for gene transcription and cell function. In short, we hope to provide an overview of the different ways that steroid hormones influence neuronal function, and will conclude by examining how different modes of steroid hormone signaling affect behavior.