This special session focuses on simulation tools and real-time simulation applications used in and for evaluation, management, and design of Intelligent Transportation Systems (ITS), as well as Smart Cities. Such simulations are expected to offer prediction and on-the-flow feedback for the better decision-making, bringing up means for both the imlementation of more complex traffic management systems and end-user applications. Off-line and real-time analyses of data collected from infrastructured systems (e.g. real-time traffic information), mobile, distributed technologies (e.g. communication devices), and socially-build systems (e.g. social networks applications) are of great interest for shaping and influencing how ITS solutions are designed. Thus, we are particularly interested in how these data and technologies can be incorporated in domain-related models and simulations. We aim to bring together experts from both industry and academia to discuss the challenges related to modelling and simulation for ITS.