Early Childhood Intervention (ECI) for vulnerable children between the age of 0-3 and 6 can be seen as well established preventive service in Europe. Even though recent epidemiologic data indicate higher rates of vulnerability during childhood and adolescence, traditionally up to 6% of the children are eligible for the ECI treatment. Definitions describing the ECI include from stable or ad hoc trans-disciplinary teams helping the child, to specific professional profiles. There is a scientific consensus regarding the effects of the ECI upon the child’s development and the family dynamics. The ECI itself is responsible for more stable impact on the socio-emotional development of the child and the parent-child relationship. Specific focus in the research is given to the role of the parents as primary caregivers. Based on the importance of enhancing the interactions between the parents and the children, this paper discusses the strategies that help increase the efficiency of the ECI trough parental involvement. Special attention is dedicated to the mutual understanding, transparency and the use of common language such as the ICF.