"Words and Concepts" is a computer software program that focuses on building oral language skills related to vocabulary, comprehension, word relationships, and other concepts in six units--vocabulary, categorization, word identification by function, word association, concept of same, and concept of different. It can be used by adults and children with varying special needs, including language-learning disabilities, developmental disabilities, physical impairments, hearing and vision impairments, and autism. One study of "Words and Concepts" met the What Works Clearinghouse (WWC) evidence standards. This study included 78 preschool children from Roanoke, Virginia, and examined intervention effects (that is, "Words and Concepts" either with or without enhanced interactions versus a comparison group) on children's oral language. The children studied were from economically disadvantaged families, and some received additional speech-language services--a clinician provided lessons focused on improving speech--at the time of the study. This report focuses on immediate posttest findings to determine the effectiveness of the intervention. One study reviewed by the WWC investigated the effects of "Words and Concepts" in center-based settings. The study (Schetz, 1994) was a randomized controlled trial that met WWC evidence standards. Schetz (1994) included 78 four-year-old low-income children attending five Head Start classes in Roanoke, Virginia. The study compared oral language outcomes for children participating in two intervention groups--the "Words and Concepts" series with enhancement (that is, software with programmed instructional interaction with a speech-language clinician) and the "Words and Concepts" series without enhancement (that is, software without the programmed instructional component)--with children in a no-treatment comparison group who received language enrichment from their regular Head Start curriculum. Because the WWC is interested in the overall effectiveness of "Words and Concepts" and not the mode with which it was implemented, the WWC combined the two intervention groups into one group and derived the rating of effectiveness by comparing the oral language outcomes between the combined group and the no-treatment comparison group. Schetz (1994) conducted a separate analysis comparing the outcomes between the two intervention groups--comparison of "Words and Concepts" with enhancement to "Words and Concepts" without enhancement--which does not allow the effects of "Words and Concepts" to be determined but does test the effects of using enhancement with the program. The results from this separate analysis do not factor into the intervention ratings, but are discussed separately and presented in Appendices A5.1 and A5.2. Based on this study, the WWC found no discernible effects for oral language. Findings also suggest that implementing "Words and Concepts" with or without enhanced interactions with a clinician does not influence the impact of the program on children's oral language skills. The evidence presented in this report may change as new research emerges. (Contains 6 footnotes.) [This publication was produced by the What Works Clearinghouse. The following study is reviewed in this intervention report: Schetz, K. F. (1994). An examination of software used with enhancement for preschool discourse skill improvement. "Journal of Educational Computing Research," 11(1), 51-71.]