This paper presents the results of a design process for new integrated land use and transportation models recently completed for the Puget Sound Regional Council (PSRC). The design process began with an analysis of policy requirements and assessment of the current models in use at the PSRC and nationally, and used an iterative and participatory approach to ensure that model requirements were clearly identified and that the proposed model design would address these requirements. The development of the model requirements drew on a broad survey of the literature and of operational models, and the proposed model design offers a unique approach to the development of a new land use and travel model system that corresponds to a behavioral integration of the choice processes across relevant time frames.