This study reports on efforts over several years to design and implement a yearlong intervention intended to support secondary mathematics teachers in their early years of teaching. The intervention is designed to retain early career mathematics teachers in the professions by engaging them in the development of meaningful professional relationships with a school-based mentors, and by creating an online community of practice for support with other professionals. The intervention itself consists of early career teachers and their mentors participating in monthly professional learning activities such as online meetings, videoconferencing panels with experts, and collaborative reading and discussing timely, purposeful, and relevant content. The intervention is designed to not over burden the participants and to be feasible for national implementation with little to no funding. This article presents the purpose, design, and implementations of the intervention, as well as a discussion of challenges faced and potential next steps and future directions for similar work.