This chapter extends the basic two-level univariate regression model to a threelevel univariate model and several multivariate models. First, we develop a series of models to explain variability in a random intercept and slope across level-3 units. We illustrate how to develop the successive models using Mplus input files and how to evaluate their suitability. Second, we develop a multivariate model with two outcomes and extend this to a multilevel path model with mediating variable. In this latter type of model we illustrate how to use the matrix specification in Mplus for specifying multivariate multilevel models.