Poor post-school outcomes for youth with disabilities have consistently been reported internationally. Interagency collaboration between school systems and post-school services is critical and key to improving post-school life for these youth. An initial Queensland study that benchmarked the teacher practice of 104 transition teachers and associated personnel indicated that interagency collaboration practices had the lowest levels of implementation. These results were the motivation behind a second study which investigated the hypothesis that lack of teacher control over interagency collaboration practice formed a roadblock for effective transitioning of youth with disabilities. Results generally confirmed the hypothesis and provide further understanding about the multi-faceted nature of interagency collaboration and the stakeholders involved in this process. Three interconnected actions are proposed to bypass identified roadblocks. If these actions are put in place, schools should improve their connections with post-school services, teachers should enhance their practice, and students should achieve improved post-school outcomes.