This article explores the potential for addressing issues related to improving the sustainability and safety of a city's transportation system. The study demonstrates the need for a comprehensive approach that considers not only the direct but also the indirect effects of potential solutions, selecting those that enhance the overall sustainability and safety of the system. The article presents a conceptual model of such a system and illustrates implementation methods using a large city as an example. Furthermore, it demonstrates how simulation modelling can address urban transportation network issues and quantifies the impact of implementing the proposed solutions. As a specific case, the research focuses on optimizing parking management-a critical factor in urban mobility. A simulation-based Decision Support System is proposed, with a microsimulation model developed in AnyLogic for the parking area of a children's educational center. By comparing the baseline ("as-is") situation with a managed ("to-be") system featuring priority reservations, the study quantifies key improvements. The results show an 85% reduction in average parking search time for teachers and a 62% reduction for visitors during peak hours. Furthermore, the optimized system achieves a 65.9% decrease in associated CO2 emissions. These findings validate the model's effectiveness and highlight the significant environmental and social co-benefits of intelligent parking management within a broader "smart city" framework, contributing to reduced congestion and enhanced urban liveability.