Self-regulatory skills are essential for school readiness and future achievement, but self-regulation is a broad and multidimensional construct consisting of both behavioral and cognitive processes. Thus, researchers often study these processes from either a behavioral and temperament-based approach or a cognitive/neural systems approach. The temperament-based framework often focuses on effortful control, whereas the cognitive or neuroscience framework often focuses on executive functions. Although literatures on effortful control and executive functions come from different research traditions, the field needs to view them as complementary rather than incompatible to advance the understanding of the role of self-regulation in learning and achievement across development. This article calls for bringing both bodies of research to the table when making decisions about educational policies and practices.