The temporal resolution of today''s simulated scientific data sets is constantly growing. Simulations spanning thousands of discrete time steps are common these days; simulations with a much higher resolution exist. The growing amount of discrete time steps leads to significant problems, particularly concerning the navigation through such data sets. This book presents a set of techniques (from 3D user interfaces to parallel computing) that together enable an intuitive, interactive, and accurate navigation through time-varying scientific data. Because Virtual Reality (VR) has shown to be an effective tool in the analysis of complex, spatio-temporal phenomena, the focus lies on analysis scenarios within virtual environments.