There are three major examples of collaborative programs between certified nurse-midwives (CNMs) and obstetrician-gynecologists at Baystate Medical Center in Springfield, Massachusetts, within the Department of Obstetrics and Gynecology. One program is a midwifery practice that serves a diverse population in a hospital-based office, four neighborhood health centers, and a correctional facility. Another program provides a triage function for patients who present to the hospital with obstetric or gynecologic problems. The third program introduces a team approach to the education of residents with a CNM having primary responsibility for teaching normal obstetrics to first-year residents and medical students in collaboration with attending physicians. Keys to success include an understanding of the principles of collaborative practice, the use of a detailed practice agreement between midwives and attending physicians, keeping open lines of communication, understanding and accepting differing philosophies of practice, and, most importantly, maintaining trust across all levels of providers.