The work discusses the effectiveness of dolphin therapy in two projects in Israel and Florida, where a total of 193 multiply disabled children were examined. Both qualitative and quantitative data were collected to capture the changes. This included information from parents, external assessments, pediatric neurological examinations, and the microanalysis of video recordings of human-animal interactions. Additionally, the questionnaire survey assessed the participants' competencies in cognition, emotion, motor skills, as well as the reduction of behavioral problems in a pre-post follow-up design. The results obtained show significant improvements in all areas, regardless of the specific disorders. The most impressive finding of this work is that the improvements achieved in almost all areas not only remain stable but also experience further growth by the time of the follow-up examination.