Phonological awareness is one of several key precursor skills to conventional literacy that develop during the preschool period. Significant amounts of research support the causal and predictive relation between phonological awareness and children's ease of learning to decode and spell. However, many preschool curricula and early childhood educational and caregiving settings are still lacking in robust instruction in this area, and many preschool instructors do not yet have a strong grasp of the developmental trajectory of phonological awareness nor of how to incorporate effective support and instruction into a developmentally appropriate teaching plan. This article summarizes what is known from high-quality research about the development of phonological awareness and about how this informs effective pedagogical strategies for its instruction. Numerous examples are given of effective instructional strategies derived from randomized trials of preschool curricula and interventions. (Contains 1 figure.)