Based on the assumption that a knowledge of child development is essential when planning an early childhood program, this booklet provides information on the typical development of children from birth to two years. The booklet begins with a description of stages of physical, mental, and social development and presents a chart illustrating the variation in the appearance of developmental milestones, such as locomotion. Section 1 of the booklet addresses physical development, describes ways to create a safe, stimulating environment, discusses the importance of play for development, and suggests toys to enhance development. Section 2 briefly discusses intellectual development and language acquisition and focuses on the importance of talking and reading with infants. Section 3 addresses social and emotional development, focusing on emotional expression and learning. (KB)