As a newly recognized subspecialty, the field of hospice and palliative medicine (HPM) must transition existing pathways for board certification, fellowship standards, and fellowship accreditation to one based on the Accreditation Council for Graduate Medical Education and American Board of Medical Specialties competency framework. The Competencies Work Group of the American Board of Hospice and Palliative Medicine, using an iterative process informed by the field, has developed a set of Initial Competency-based Outcomes for the HPM Subspecialist. These competencies will set the standard for the "competent hospice and palliative medicine subspecialist physician," guiding future HPM fellowship training and potential midcareer HPM training opportunities. Lessons learned are highlighted. © Mary Ann Liebert, Inc.