Alternative preschool programs are more and more present in kindergartens, in Croatia as well as in the world, showing extraordinary results in work with children. Researches show that alternative preschool programs have positive influence on child's development, but parent's attitude and content are rarely tested. This thesis describes implementation of Montessori program sin kindergartens, it's influence on children's development and questions parent's opinion, their content with the program, as well as their cooperation with the institute of early and preschool care and education. The aim of this thesis was to present elementary principles of Montessori pedagogy and moreover to determine in which amount are the parents of the „Cekin“ kindergarten familiar with the Montessori program and it's methods in the preschool institute, as well as their content. The research was conducted through questionnaires for 49 parents whose children attend the Montessori program in „Cekin“ kindergarten. Conducting the research in this thesis it is concluded that the parents are extremely satisfied with the kindergartens' work, even though only one third of them are familiar with the Montessori pedagogy, as well as it's working equipment. Children of the „Cekin“ kindergarten show the most interest in practical activities from everyday life, as well as in creative expressing, in any of art, music or scenic forms. On the contrary, children show the least interest in Mathematics, especially geometry and calculating operations, even though they find numbers interesting. Additionally, the parents have particularly positive opinions about educators in „Cekin“ kindergarten, with whom they have exceptional cooperation which helps building child-safe environment. All the results, given by the research in which the parents participated, are very valuable for „Cekin“ kindergarten, hence they prove cooperation, which is one of the most important component of care educational work in preschool institution.