Nonprofit organizations rely on a combination of volunteers and staff for their operations. Determining the optimal policy for sharing work schedules among volunteers and staff is a complex task. Organizations have unique workforce compositions and operational scheduling policies. Policies differ in the order of scheduling activities (e.g., staff first or volunteers first) and the ways in which tasks are allocated to staff. In this work, we identify key characteristics that influence the optimal shared-scheduling policy. We propose general policies and models to define the optimal scheduling policy. We evaluate the performance of these policies using four metrics that consider both organizational needs and volunteers’ satisfaction and retention. This research aims to provide organizations with insights into the optimal shared-scheduling policy that aligns with their operational goals while keeping their volunteer workforce engaged.