The evaluation of people with special educational needs is based on complex knowledge in medical, psychological, educational and social terms, covering the entire issue encountered by them in everyday life. It should be emphasized that, in the vast majority of cases, evaluation is a continuous process, and not an instant x-ray of the subject's condition, requiring prolonged collaboration, differentiated between members of the evaluation team and the person with special educational needs. The complex assessment of children with special educational needs correlates a series of data obtained by anamnesis, medical diagnosis (clinical and paraclinical) and psycho-pedagogical diagnosis (using methods such as observation, conversation, questionnaire, survey, application of tests or experimental trials, etc.) in following this evaluation, a formative diagnosis is established (which also includes a differential diagnosis) and school guidance documents are drawn up. Thus, based on the operational psychological theories elaborated by J.Piaget and L.S.Vygotzski (the area of the next development), the evaluation and diagnosis activity is transformed from an ascertaining activity into an investigative-ameliorating activity of research-action type. In this way, the evaluation and diagnosis of children with special educational needs become a complex, unitary, dynamic and long-lasting process, which aims to facilitate the development and application of compensatory and recovery therapeutic approach, school guidance of the child in optimal conditions, promoting school integration and socialization and normalization of the child's life.