Imagine we had a common mobility card for Chennai and I took a bus and then switched to Metro. How much of the fare I pay will go to MTC and how much to Metro? Since all public transit would be using the common card, all the fares would go to one account. Then it has to be accurately and efficiently redistributed. With some public transit managed by the Centre and others by the state government, and some as partnerships between the two, this is a complex process! (Even if a Common Mobility Card were to be implemented, it is essential that the more traditional payment methods are retained to ensure that all user groups feel confident accessing all public transit systems). Reliability, accessibility and convenience need to be kept at the heart of any planning mechanism.