The study focuses on the negotiation of identities during conflict situations in the context of pediatric appointments for children and teenagers diagnosed with Attention Deficit Hyperactivity Disorder (ADHD), in routine care conducted by the doctor. The main purpose consists on creating intelligibilities about the family conflicts resultant from the disorder and the identities projected/negotiated by the parents, children and teenagers with ADHA, for themselves and others. The research is based on theoretical lines of speech-in-interaction regarding clinical care. It is situated on Professions Applied Linguistics, in articulation with the Ethnomethodological Conversation Analysis, in an institutional context, in Interational Sociolinguistics and on discursive studies about identities. The research methodology, of a qualitative and interpretive nature, with video recording of four pediatric appointments, has an ethnographic character, by a participant observation in the Doctor’s office waiting room. Data were transcribed in accordance with conventions of the Ethnomethodological Conversation Analysis. The analyzes results indicate the professional practice of the Doctor concerning clinical care and the psycho-educative orientation. The Doctor carries out activities related to physical evaluation and behavior tasks of children and teenagers, in actions that aim at the ADHA medicated and psychological treatment, and also the communicative acts as a formulator, mediator and advisor when intermediating conflicts emerging from the ADHA, family and school inter-relation, resultant from the behavior of the children in family relation and the their low academic performance in the school context. The parents align with the Doctor, in the framings of their children school disorders, and stablish conflicting framings together with their children; they project to themselves the identities whose attributes oscillate between participative, comprehensive and responsible, and impatient, frustrated and exhausted. The identities that project toward children are occasionally presented as contradictory, among the children considered lovely, insightful and annoying; and intelligent, inept and ungracious students. Children and teenagers, although being aligned with the Doctor, in the framings of appointments and orientation reject the ADHA stigma and project to themselves the identities of students and children considered to be respectful and intellectually capable; and for their parents, most of the time, identities of impatient and demanding parents regarding education. The study provides a greater understanding of the complexity and the multiple activities of the professional performance of the Doctor during the pediatric care, and contributes for a better understanding of the daily experiences of parents, children and teenagers with ADHA, marked by destabilizing conflicts of harmony between these social authors in the school and family contexts.