Objective data on the development of stuttering during its first several months are sparse. Such a deficit is due to parents' tendency to postpone professional consultation regarding early stuttering until later in the course of the disorder and to a lack of longitudinal studies beginning close to onset. This report presents information on a rare group of 16 preschool subjects who were evaluated within several weeks after stuttering onset and followed for 6 months using multiple measures. The findings show that often early stuttering takes on a moderate-to-severe form. Substantial changes occurred, however, during the 6 months of the study, with a strong tendency for reduction in stuttering-like disfluencies, number of head/face movements, clinician severity ratings of stuttering, and parent ratings of stuttering. Several subjects, including severe cases, exhibited complete recovery. The large changes that occur during the early stage of stuttering suggest that relatively small differences in the length of post-onset interval (stuttering history) can greatly influence all research data of early childhood stuttering. The high, as well as fast, improvement rate suggests that the precise timing of early intervention should be conscientiously evaluated in carefully controlled studies.