For the past 10 years, the Northeast Center for the Application of Prevention Technologies (NECAPT) has provided technical assistance services to Single State Agencies (SSA) for substance abuse prevention. As Federal prevention initiatives have come and gone during this time, States have had to conform to new prevention requirements while at the same time try to build effective prevention systems. NECAPT's TA methods vary - dramatically at times - based on the type of State TA system that is currently in place. Some states have no formal TA system while others have coordinated and multi-faceted TA and training structures. Resources vary across states as does the value placed on TA infrastructure. The success of Federal prevention initiatives relies heavily on the type of TA system that exists within a State. Drawing on experiences in four States, this presentation will provide some history and context for the development of these systems, discuss challenges States face in integrating new initiatives into their systems, and present a typology of TA systems, specifically in the context of the Center for Substance Abuse Prevention's Strategic Prevention Framework State Incentive Grant. We will discuss retrospectively how this TA structure has impacted NECAPT's service delivery, resulting challenges, and solutions to these challenges. Drawing on a review of the literature on contributing factors in the development of effective TTA systems, we will provide recommendations for other TTA and resource centers in addressing these real challenges that States face in implementing systems change.