The present study examined individual differences in trajectories of self-regulation among 459 Spanish-English dual-language learners who were Hispanic from 4 different samples and 3 geographic locations in the United States. Self-regulation was assessed in all samples using repeated administration of the Head-Toes-Knees-Shoulders (HTKS) task from early childhood through early elementary school. Results of latent growth curve analyses revealed that growth was best represented by quadratic trajectories. Latent class growth analyses captured significant individual differences in self-regulation trajectories. (author abstract)