Arizona State University will implement a Dialogic Reading, Inferencing, Vocabulary Enhancement, and Scaffolded Conversations (DRIVES) professional development (PD) program which aims to increase high quality language and emergent literacy instruction in English and Spanish by providing PD to Head Start teachers, mentors, assistants, and specialists. The DRIVES PD program goal is to improve academic outcomes of children who are English Language Learners (ELL) in Head Start. Specifically, this program will target skills found to improve ELL children's reading, oral language, and decoding. This program will focus on increasing vocabulary, language comprehension, and complex language production through: (a) scaffolding conversations, (b) high-level questioning, (c) direct vocabulary and story retelling instruction, (d) repeated and dialogic reading, and (e) systematic use of English as a second language instructional strategy. During Year 1, the PD program will be developed. During year 2, 18 classrooms will be randomly assigned to intervention (immediate treatment) and control (delayed treatment) groups. During Year 3, the control group from cohort 1 will become the intervention group for cohort 2 and nine additional classrooms will be randomly assigned to the control group. In addition, in Year 3 DRIVES will be evaluated for sustainability. Results are expected to increase ELL children's outcomes in vocabulary development, inferencing skills, story telling, and language comprehension and production skills in English and Spanish. In addition, the DRIVES program will benefit Head Start staff by providing high quality oral language instruction in the classroom.