The aim of the study is to analyze the clinician’s alliance with parents during the diagnostic process in relation to therapeutic compliance and clinical evolution of individuals aged 0–11 years. The sample was formed by 84 individuals aged 0 to 11 years (18 < 6 years, 66 aged 6 to 11 years; 62 males and 22 females) who came to the Neuropsychiatric Unit for Children and Adolescents for a consultation regarding psychorelational and behavioral problems. Neuropsychiatric consultation took place in five diagnostic interviews with child and parents, separately. The last session was devoted to communication of psychiatric diagnosis (according to ICD 10) and therapeutic suggestions, if any. The clinician’s relationship with parents and patients’ participation were evaluated in terms of collaboration and quality of interaction, on the basis of pre-established criteria. Data about patients’ therapeutic compliance and clinical outcome were collected during a follow-up visit eight months after the last session. Results suggest that the better the alliance between parents and clinician, the higher the therapeutic compliance and the likelihood of a positive outcome for patients. Our data suggest that good communication with parents benefits child patients, both in terms of response to the parents’ need to report their children’s worrying behavior and as a response to the discomfort expressed by children when they come in for consultation.