Hyperemesis gravidarum is an infrequent, yet significant, maternal complication of pregnancy. Beginning with the frequently experienced nausea and vomiting of pregnancy, symptoms can progress to hyperemesis, a debilitating condition affecting maternal and fetal well-being. A basic understanding of the pathophysiology of the disease process and an awareness of the therapeutic interventions that are available will facilitate midwifery planning for either the collaborative care or the potential referral to medical management, both of which may be required with this clinical entity. The diagnosis and initial management of hyperemesis is within the purview of midwifery care. As certain critical features of duration and severity evolve, medical collaboration and ultimate hospitalization may be required. For those few individuals requiring the most intense level of care, the critical support and encouragement afforded by midwifery participation will contribute to timely resolution of this debilitating condition. This article discusses the continuum from differential diagnosis to ultimate care of the woman who has excessive nausea and vomiting of pregnancy. Collaboration among health care providers will allow all to exercise their respective skills in achieving the optimum in safe therapy and support for their patients.