Workplace voice is well-established and encompasses behaviors such as prosocial voice, informal complaints, grievance filing, and whistleblowing, and it focuses on interactions between the employee and supervisor or the employee and the organizational collective. In contrast, our chapter focuses on employee prosocial advocacy voice (PAV), which the authors define as prosocial voice behaviors aimed at preventing harm or promoting constructive changes by advocating on behalf of others. In the context of a healthcare organization, low quality and unsafe patient care are salient and objectionable states in which voice can motivate actions on behalf of the patient to improve information exchanges, governance, and outreach activities for safer outcomes. The authors draw from the theory and research on responsibility to intersect with theories on information processing, accountability, and stakeholders that operate through voice between the employee-patient, employee-coworker, and employee-profession, respectively, to propose a model of PAV in patient-centered healthcare. The authors complete the model by suggesting intervening influences and barriers to PAV that may affect patient-centered outcomes.