Kevin J. Grimm, PhD, is Associate Professor in the Department of Psychology at Arizona State University, where he teaches graduate courses on quantitative methods. His research interests include longitudinal methodology, exploratory data analysis, and data integration, especially the integration of longitudinal studies. His recent research has focused on nonlinearity in growth models, growth mixture models, extensions of latent change score models, and approaches for analyzing change with limited dependent variables. Dr. Grimm organizes the American Psychological Association?s Advanced Training Institute on Structural Equation Modeling in Longitudinal Research and has lectured at the workshop for the past 12 years.