The process of adapting to the new and unknown is challenging for every individual. From the first day, the child encounters various unknowns and new experiences. One of the first independent steps for a child into the unknown is an encounter with an educational institution. The adaptation of a child to an educational institution is a complex process that begins with starting a nursery. In the period of adaptation, the child gradually gets used to the educational institution in which he establishes a socio-emotional connection with the educator. The child experiences a very stressful adjustment period with a lot of crying, aggression, disinterest, possible refusal of interaction, passive behavior and avoidance of contacts and problems with feeding and sleep. In addition to the level of emotions, the child can also show physical reactions, such as abdominal pain and vomiting. The time duration of adaptation is different for each child and lasts depending on the child's individual characteristics. One of the factors that depend on the duration of adaptation is the form of attachment that the child has achieved with his primary caregiver, i.e. Mother. Surely attached children will cope with the process more easily because they have been taught that a parent will be available to them when they return and give them comfort. It is impossible to fully prepare the child in such a way as to avoid difficulties during adaptation, but it is possible to reduce them by preparation. The preschool teacher, child, parents, professional team and other employees of the early and preschool education institution must be actively involved in the adaptation. In this process, the educator guides and directs the entire adaptation: creates a quality environment, interacts and provides support to the child and parents, experiences the emotions of all participants in the process and helps them feel safe and accepted in the new environment. The paper presents the process of adaptation of a child to an educational institution and shows the importance of all other participants in the process.