This study examined previous literature that described approaches to interagency collaboration and identified the most appropriate practices to implement while working with transition-age youth with disabilities and their families. Within this qualitative content analysis review of literature on interagency collaboration, we used the theory of working alliance and its three categories (i.e., goals, bonds, tasks) to support best practices in interagency collaboration for youth with disabilities. Twelve themes were developed to support the three categories and define how stakeholders could create successful interagency collaboration. These themes can be used to provide guidance for best practices to inform successful interagency collaboration among those involved in the transition planning process. Limitations and implications for future research and practice are discussed.