This article discusses the importance of political action by three associations of mental health care users and family members: the Brazilian Association of Mental Care Patients, Friends, and Family (AFDM), the Society of General Services for Occupational Integration (SOSINTRA), and the Association of Relatives and Friends of Patients in the Juliano Moreira Psychiatric Facility (APACOJUM). Our aim is to increase the visibility of these associations and to foster innovation and collective forms of solidarity and mutual help in the health care field. The article analyzes the associations as special interest groups within a specific arena, the Rio de Janeiro Municipal Health Council.