Unlike print, screen-based design doesn't only allow for two-dimensional, static images. New technologies have enabled the screen designer to create moving imagery, both two-dimensional and three-dimensional. Such developments have led to the need for new grid systems, as it is just as important to have these moving images in an orderly fashion as it is to design a book in a coherent fashion. However, with moving imagery, designers have to be aware of the fourth dimension, time. This book provides a comprehensive exploration of the moving image and the grid systems to support it. As well as discussing the fundamental elements of space, volume and motion in time-based media, the book and accompanying CD-Rom examine more advanced grid system applications such as grids for interactive media, tracking systems and those which synchronise speech, sound and movement. This book is relevant to anyone working with images in a time-based media, be they students or already established professionals.