Teaching sign language--to deaf or other children with special needs or to hearing children with hard-of-hearing family members--is not new. Teaching sign language to typically developing children has become increasingly popular since the publication of "Baby Signs"[R] (Goodwyn & Acredolo, 1996), now in its third edition. Attention to signing with babies has received much publicity. Language development is so important to success in school and in life that accurate information for families, caregivers, and other educators is crucial. This article begins with a brief history of sign language and a review of normal language development. It then reviews the research on the effects of sign language on hearing children's language development and the overall benefits of signing with babies. (Contains 1 figure and 2 tables.)