The technology for creating an Acoustic Virtual Reality for wide variety of applications has been developed in the last decade. An important requirement of Virtual Reality is the multimodal approach which includes vision, sound, tactile and haptic stimuli. The process of creating a physical stimulus based on computer data is called "rendering". The development of rendering and reproduction of acoustic stimuli in VR is now at a stage where integration of spatial room sound is feasible by using PCs. This applies to multi-channel binaural synthesis as well as to full room-acoustic simulation algorithms. In this chapter the basic concepts of real-time room acoustic simulation, early reflections' and spatial reverberation rendering, binaural reproduction technology and dynamic realtime audio signal processing are presented.