*Providing tools for measuring change over time, longitudinal SEM is a hot topic for researchers and students using today's sophisticated statistical software programs. *The first authored book to fully articulate the use of SEM for longitudinal data. *Emphasizes a decision-making approach, uses well-chosen metaphors and examples from real research, and includes loads of tips on what works--and what doesn't work. *Written by a popular teacher who gives workshops on the topic worldwide (most recently in Finland, Germany, and Greece). *Online supplement: utility is enhanced by data sets and other resources provided at the companion website.