Inmates in American prison began demanding their right to be heard in the 1960's. At this time, courts became more willing to act where correctional practices appeared to be in conflict with constitutional rights. Formal mechanisms for dealing with inmate complaints generally fall into three broad categories: ombudsman programs, inmate councils, and multilevel grievance procedures. The ombudsman system, which originated in the Scandinavian countries, is based on the appointment of an individual to handle complaints inmates have with the institution. Inmate councils involve an elected body of inmates who work to resolve problems through regular meetings with administrators. The more traditional approach to dealing with inmate complaints is the multilevel grievance procedure system. Regardless of the model followed, experience indicates that six principles must be adhered to for the mechanism to work. These six include a written response to all complaints, reasonable time limits for responses, outside review, participation of inmates and line staff, easy access with guarantees against reprisal, and broad jurisdiction. All satisfactory grievance mechanisms incorporate the concepts of participation, fairness, and justice. The chapter provides 16 reference notes.