The urban mobility sector is developing at a fast pace and is demanding transportation systems to be resilient and sustainable. Policy makers deal with an extensive offer of new technologies but lack an overview of the contribution of these mobility solutions to their urban planning ambitions. Uncertainty exists regarding both the technological advancements and the future of the mobility sector in a more general sense. Hence, there still seems to be a challenge to overcome for policy makers to transform the mobility system and adapt to the developments. The applications are clear and literature on implementation is present, but no specific guidance in terms of trade-offs is available to governmental organizations working on urban infrastructure. This is also shown by a lack of literature on decision support systems for smart mobility. On top of that, there is a more practical motivation for a tool that provides an overview on the possibilities in smart mobility applications and their effects. Engineering and consultancy firm Witteveen+Bos requested a design for such a tool, to be able to provide more insightful advice on smart mobility solutions to their clients. The present study concerns the development of a tool that gives insight in the (expected) effects of investments in different smart mobility solutions The research question is formulated as: What is a useful tool for policymakers to quickly assess effectiveness and efficiency of smart mobility applications? The tool designed assesses the mobility situation in a municipality, suggests smart mobility applications that are relevant in regards to specific mobility ambitions, and has set the first steps for a framework to assess the effects of smart mobility applications. On top of that, the tool is verified by testing for all user and system requirements that were set by consulting policy makers and experts, evaluated by means of a walk-through of all the units in the tool, and validated with the envisioned users to evaluate if the tool is relevant and supports their decision-making process.