Autism spectrum disorder has been defined differently throughout history, and to date the legal basis has changed and in the Republic of Croatia it has been defined in accordance with legal regulations. In order to more effectively approach the diagnosis of autism spectrum disorders, a number of experts are needed who will contribute their knowledge, skills and acquired abilities to the analysis, communication with each other, cooperation and use of different methods for early detection of autism spectrum disorders. One of the methods/ interventions for autism spectrum disorders is early intervention. Early intervention is the first step for parents to first receive professional help and support and, with the help of experts, to enable a simplified and accelerated process of obtaining adequate help for the child and the family as a whole. Transdisciplinary is one of the models of teamwork that aims to effectively support the child and family in early intervention. In addition to providing a family support system, transdisciplinary leads to a lower level of parental confusion and allows for more coherent intervention plans. Parents play an important role in the whole process of early intervention, so their response is the most important, and it leads to the application of the process of early intervention. The role of other professionals, from the point of view of their profession, is essential for each expert to contribute and knowledge from the professional point of view of one (his) discipline.