Passengers' choice of mode in public transport depends on several other factors than travel time. In order to increase public transport usage, transport service should be designed in a way that it accommodates the service levels required by customers. Despite being one of the most important determinants of public transport demand, convenience is often neglected in transportation systems design and assessment of operational performance. This study is an attempt to provide a better definition of comfort in public transport and to develop a framework for measuring perception of comfort, one of the most important determinants of public transport convenience. This paper offers a new method for assessing comfort in public transport systems by introducing a new index which is based on a number of qualitative and quantitative indicators. It also provides a deeper understanding of passengers' attitudes towards public transport and perception of comfort in public transport services. (C) 2017 The Authors. Published by Elsevier B.V.