In this research three new innovative concepts are introduced and developed: the first defined as Transit System Maturity Components (TSMC), the second referred to as Transit System Maturity Scale (TSMS) and the third labeled as Transit System Maturity Index (TSMI). The TSMC is meant to conceptualise the main strategic generic components characterising the maturity of transit systems. The TSMS is an S shaped scaling system for measuring maturity of transit system components. The TSMI presents an innovative index meant to assess the overall level of maturity of a city transit system. Such framework is envisaged to be used to determine and compare the overall maturity levels of transit systems in cities of the world as well as to act as a basis to identify strengths & gaps that need to be addressed/completed. Furthermore, it can also act as an ingredient in shaping and developing future road maps for transit system in cities across the world. The research concludes by demonstrating the applicability of TSMC, TSMS, and TSMI in conducting an initial assessment of the Transit System Maturity for the fast growing city of Dubai.