Written at an intermediate level this book will appeal to researchers in education who have had an introduction to statistical ideas and who are interested in applying up-to-date statistical methods to their own data. The emphasis is on methods which recognize that educational data are often 'hierarchical' or 'multilevel', often 'longitudinal', usually 'observational' rather than 'experimental', often 'categorical' and usually having no fixed scale. The material is introduced through the use of examples based on real data. The data sets are included on disk and there are student exercises at the end of each chapter.