Michael’s basic studies into the mechanisms of the action of gonadotropin-releasing hormone (GnRH) were the first to identify calcium as a key second messenger to GnRH’s activation of its cognate receptor on the gonadotropin-producing cells of the anterior pituitary. His demonstration of the mechanisms of homologous receptor desensitization supported the development of a large number of GnRH analogs. His research program cleverly integrated disparate avenues of information to inform his work. These varied from ongoing studies of the physiology of GnRH in humans and primates, the peptide chemistry of GnRH analogs, and the cell biology of hormone action in G-protein-coupled receptors (GPCRs) for examining their pathways of degradation, to the use of genetic mutations in patients with isolated GnRH deficiency. He used each of these as they became available.