The aim of the master thesis is to outline and demonstrate how animal assisted therapy (in this case therapy dogs) can yield many benefits for children's development. The effectiveness of animal assisted therapy for people with developmental disabilities can be best measured by increased quality of life, communication skills and enhanced ability of self-care. The relationship between therapy dog and the child is extremely important because it sets the tone for further collaboration, and each “child-therapy dog” relationship should be treated individually. It is important to understand the character and behaviour of each child separately, especially of those with special needs. Hence, this master thesis we will look closer into exactly this topic: children with special needs and therapy dogs. Children with developmental disabilities face many difficulties and obstacles, yet they are presented with wide range of opportunities. Whether the child will grasp an opportunity will highly depend on its environment: forth most parents, therapist, friends. All people are born with same basic needs, but to address those of children with disabilities, a therapy dog by their side would be seen as highly beneficial for their further development. Using dogs for therapeutic purposes, engaging them in educational processes or organizing visits to specialized institutions are all considers to be rather new ways of supporting children with development disabilities and are yet to be fully accepted by wider public. Nowadays, the usage of animal assisted therapy is gaining more popularity and traction thanks to early adopters who were eager to implement new and potentially better ways of counselling and providing therapeutical services. It is important to foster the connection of the therapy dog and the client in the right way in order to maximize the rate of success, that is development of the child. Also institutes and centres in the Republic of Croatia which actively use assistance dogs and therapy dogs in their daily work will be introduced. Lastly, the thesis will focus on Bella - the first therapy museum dog that’s used for providing services in the area of Vinkovci, Vukovar-Srijem County and Osijek-Baranja County. Bella and her mentor Iva never left anyone indifferent with their approach.