In this paper we describe applications, research issues, and approaches related to Intelligent Transportation Systems (ITS). More specifically, we focus on spatio-temporal databases in urban transportation. ss the issues of trip planning and navigation, abstraction of concepts from spatio-temporal sensor data, mobile peer-to-peer data management, and social networks and crowd-sourcing. These issues are strongly related to ITS efforts currently undertaken throughout the world, particularly the IntelliDrive initiative of the US Department of Transportation.