The analysis of data in the form of directions in space, or equivalently of positions or points on a spherical surface, is required in many contexts in the earth sciences, astrophysics and other fields. While the contexts vary, the statistical methodology required is common to most situations, and has been developing rapidly over the last three decades, so that a large body of results and techniques is now disseminated throughout the literature. This book aims to present a unified and up-to-date account of these methods for practical use. The emphasis is on applications with the statistical methods being illustrated throughout the book by data examples from many of the relevant fields. Particular care has been paid to the computational and computer aspects of the procedures, so that there is no gap between the presentation of a technique and its implementation.