Computer controlled systems are almost omnipresent nowadays. We expect such systems to function properly at any time we need them. The malfunctioning of home electronics just irritates us, but glitches in a car, power plant or medical support system may threaten life, and faults in nuclear missile control facility may bring the end to civilisation. Such ubiquity of computer based control puts very high reliability requirements on such systems. Hybrid systems combine continuous real-time behaviour and discrete events. Research in hybrid systems aims at providing means for reliable design and production of hybrid systems. In this thesis we explore the world of hybrid systems. We acknowledge relevance and complexity of hybrid systems research, and emphasise several different research topics: modelling, analysis, testing and deployment of hybrid systems.