Interactive writing has been recognized as a potentially effective instructional method for increasing alphabet knowledge skills of kindergarten and first grade students. The current study addressed the lack of experimental research regarding the use of this strategy in the preschool setting. A pretest/posttest control group design was used with 73 Head Start students to examine the effects of interactive writing on acquisition of upper case, lower case, and letter sound identification skills. An ANCOVA statistical model was used to examine posstest scores for each outcome variable after adjusting for pretest scores and absenteeism rates. The results of this study demonstrated no statistically significant difference between the Interactive Writing group and the control group over time for each of the three outcome variables (i.e., upper case letter identification, lower case letter identification, and letter sound identification). Observed differences suggested meaningful relationships may exist between interactive writing instruction and lower case and letter sound identification. Further research is needed to detect statistically significant findings. The project described was supported by the Child Care Research Scholars Grant Program, Grant Number 90YR0060, from the Office of Planning, Research and Evaluation, Administration for Children and Families, U.S. Department of Health and Human Services. Its contents are solely the responsibility of the author and do not necessarily represent the official view of the Office of Planning, Research and Evaluation, Administration for Children and Families, U.S. Department of Health and Human Services. (author abstract)