Contents Introduction Synthesis, enzyme localization, and regulation of neurosteroids, Synthia H. Mellon Subunit specificity of steroid modulation of GABAA receptors, R.W. Olsen, E. Cagetti and M. Wallner THDOC and the GABA-A receptor, S. Vicini Neurosteoid modulation of delta subunit-containing GABAA receptor channels, M.T. Bianchi and R.L. Macdonald Potentiation and inhibition of GABAA receptor function by neuroactive steroids, L.N. Eisenman, Y. He, D.F. Covey, C.F. Zorumski, S. Zorumski, and S. Mennerick Anabolic androgenic steroids and the brain: Novel actions at the GABAA receptor and on GABAA receptor mediated behaviors, A.S. Clark, B.L. Jones, P. Yang, and L. Henderson Withdrawal effects of a neuroactive steroid as a model of PMS: Synaptic physiology to behavior, S. Smith GABA, estrogen, and sex differences in the brain, M.M. McCarthy, J.L. Nunez, and T.S. Perrot-Sinal FGIN-1-X--A series of novel specific and efficacious ligands for the peripheral benzodiazepine receptor, E,M. Skowronski-Lutz and D, Bitran GABAergic neuroactive steroids modulate selective ethanol actions: mechanisms and significance, A.L, Morrow, R, Khisti, S, Tokunaga, J,R. McDaniel, and D.B. Matthews Allopregnanolone modulates the action of ethanol and stress on the activity of mesocortical dopaminergic neurons and HPA axis, G. Biggio, L. Dazzi, and M. Serra 3a, 5a-THP's actions in the ventral tegmental area for lordosis: A model system for defining mechanisms and function of progestins, C.A. Frye and S.M. Petralia Premenstrual dysphoric disorder, I. Sundstrom-Poromaa Role of neurosteroids in epilepsy, Z. Mtchedlishvili and J. Kapur Animal models of anxiety and stress-induced behavior: Effects of neuroactive steroids, D.A. Finn, R.H. Purdy and G.F. Koob Direct modulation of amino acid receptors by neuroactive steroids: Physiological and pharmacological Implications, T.T. Gibbs and D. Farb On the neurosteroid mechanisms of action and their clinical potentials, Y. Akwa and E. Baulieu