Active travel (i.e. walking and cycling) is a promising source for physical activity, which is strongly associated with decreased risk for a range of chronic diseases and mortality.The InTHIATR project (Integrating Transport and Health in Active Travel Research) aims to contribute towards a more evidence-based planning practice for active travel.The project applies three perspectives, reflected in the three modules:A - empirical research on active travel behavior and its health effectsB - interdisciplinary collaboration on modeling of active travel and its health impacts,andC - development of a prototype tool for policy evaluation as part of planning for active travel. In Module A, InTHIATR conducts empirical research based on two cutting-edge longitudinal studies (PASTA and HoPPZürich). It investigates determinants of active travel and physical activity behavior, as well as selected short to medium term health endpoints, including injury risk.In Module B, insights from empirical research are integrated in two leading models:MATSim, a travel demand model, and ITHIM, a health impact model. The two models will be linked, and implemented in Zurich. The focus in this module is on cycling,implementation for walking is part of future plans.In Module C, a simple, user-friendly interface for above models is developed. It allows users (i.e. planners) to specify changes in terms of measures or policies, based on which the tool calculates effects on travel demand and resulting impacts in terms of health and injury risk.