With federal funding agencies such as the Institute for Education Sciences and the National Institute for Child Health and Human Development requiring that applicants use the most rigorous design and statistical applications in their proposals, it is important that researchers and graduate students have the most advanced resources at hand to understand and execute the appropriate analysis. The mission of this book is to address advances in quantitative methods such as item response theory, the family of multilevel models (including cross-classified and growth), and mixture modelling that are not covered in other texts. Each lengthy (50-60 page) chapter is self-contained and follows a common format so that readers can run the analysis and correctly interpret the output for reporting. Key Features Chapter Format Each self-contained chapter 1) introduces the analysis, 2) highlights its importance and the contexts in which it is appropriate to use, 3) contrasts the analysis with simpler, less efficient techniques, 4) demonstrates how to run the analysis using data provided by the chapter author using popular software programs, and 5) interprets the output. Expertise All chapters are written by methodological and applied scholars who are expert in the particular technique being reviewed. Audience The volume is a valuable reference tool for any serious scholar or graduate student in the social or behavioural sciences.