The thesis work I determined and compared the team work in kindergarten and school. I was interested in cooperation between a preschool teacher and an assistant preschool teacher and a primary school teacher and a preschool teacher at school. The participants and members of the team directly share roles and they are equivalent to each other. However, it is necessary to emphasize their difference in knowledge, skills and abilities. They do not have the same level of competence, motivation and work habits. Mutual cooperation and closeness and good communicational skills are necessary factors of successful team work. Team work consists of three stages: team planning, team teaching and team evaluation. In kindergarten the team work has been running for a very long time, but preschool teachers and assistant preschool teachers had different and separate tasks in the past. The introduction of the kindergarten curriculum has changed these tasks. They should jointly plan, implement and evaluate the activities. By changing education legislation in Slovenian primary schools there has also been a change in the mode of teaching. In the first grade the team work is conducted by a primary school teacher and a preschool teacher, as the second professional worker. In the theoretical part of my diploma work I define the team work, describe its special features and compare the team work between the kindergarten and school. The purpose of the study is to analyze the characteristics of the team work in kindergarten and school and compare them with each other. I was particularly interested in the team work between the preschool teacher and assistant preschool teacher in kindergarten and teamwork between the primary school teacher and the preschool teacher at school. I also presented how teams work in both environments. The main aim of my study is to examine: the organization of team work and its participants in kindergarten and school, the implementation of the three stages of team work, the complementation of each other, the division of tasks and their participation with parents. I wrote about formal equality and feelings of equivalence by the members, advantages and disadvantages of team work recognized at their work. I developed a questionnaire based on the theoretical points and set of research questions. In my research I have included 100 preschool teachers and assistant preschool teachers employed in Slovenian kindergartens and 100 primary school teachers and preschool teachers in the 1st grade of Slovenian primary schools.