One of the most challenging tasks in computer games is the generation of smooth, coherent, controllable movement. This enable us to synthesize worlds that are immersive and engaging. Worlds that are not just visually attractive' but also move and change in an aesthetically pleasing manner. This textbook is designed to introduce the reader in a practical sense to the exciting topic of animation for use in virtual environments. Organized around the central concept of motion, the book includes numerous examples in the body of the text as well as showing limitations and engineering workarounds to common problems It is also one of the purposes of this book to introduce the reader to the development aspect of games and real-time interactive software.