There is an interest from scholars and practitioners in understanding how nonprofit organizations (NPOs) can design and implement practices to enhance desirable volunteer attitudes and behaviors (Alfes et al., 2017). One important attitude is volunteers’ organizational commitment (OC). This research aims to identify factors that diminish volunteers’ OC and suggest effective ways to deal with them, which lead to NPOs performance improvement. This is achieved through a single case study in a Puerto Rican non-profit organization, which consists of in-depth interviews and self-administered questionnaires on psychological contract violation Five categories of factors that negatively affect volunteers’ OC were identified and analyzed: organizational structure, communication, recognition, strategic planning, and conflict management. General actions were provided to help NPOs deal with similar issues.