Objectives : To initiate and develop a treatment guideline in multidisciplinary approaches for related professions who are either working and/or living with children and adolescents with neurodevelopmental disorders who show behavioral problems. Methods : To collect and reflect opinions from multiple professions who assumedly have different interventions or mediations on behavioral problems, a self-report survey and Focus Group Interview(FGI) were conducted for a group of child and adolescent psychiatrists, behavioral therapists, special education teachers, social welfare workers, and caregivers. Results : According to a self-report survey and FGI results from multiple professional groups, aggressive behavior is the mostly common behavioral problem necessitating urgent interventions. However, both mainly used intervention strategies and effective treatment methods were different depending on professional backgrounds, such as pharmacological treatment, parent training, and behavior therapy, even though they shared an importance of improving communication skills. In addition, there was a common understanding of necessity to include parent training in a guideline. Lastly the data suggested lack of proper treatment facilities, qualified behavior therapists, and lack of standardized treatment guideline in the field needed to be improved for a quality of current therapeutic services. Conclusion : It is supported that several subjects should be included in the guidelines, such as how to deal with aggressive behavior, parent training, and biological aspects of neurodevelopmental disorders. Also, it is expected that publishing the guideline would be helpful to above multiple professions as it is investigated that there are lack of treatment facility and qualified behavioral therapists compared to need at the moment.