**Abstract**

Railways are one of the most used public transportation modes. Due to the low environmental impact, governments are promoting their use as a solution for mass transportation for middle-distance. Critical parameters to satisfy passengers and attract new ones are related to comfort, safety, and user conditions. Comfort is classified by dynamic and static methods, ideally combining both. The former is based on the comfort evaluation in the presence of vibration, whilst the latter is applied to standstill situations. Vibration, derived from the train motion, will be presented throughout the trip; thus, it is a major concern. For the same reason, assessing vibration levels associated with comfort gives important information about the train's condition and its major maintenance or repair needs. Vibration transmissibility allows the study of the vibration frequency that is being transmitted to the user. In this chapter, the complete seat structure and the passenger's comfort are evaluated combined with the interface pressure. This chapter presents the commonly used methodologies and results from the tests conducted on railway environment whilst running passenger service. These tests report the seat comfort evaluation and a new methodology to identify train and rail maintenance needs based on comfort analysis.

**Keywords:** railways comfort, dynamic analysis, static analysis, vibration, interface pressure
