A meta-analysis considered the impact of various methods of improving public communication skills on critical thinking. Manuscripts were obtained by searching the available electronic databases (COMINDEX, Dissertation Abstracts, ERIC, Index to Communication Journals, PSYCHLIT), various bibliographies available on the topic, as well as the reference section of manuscripts obtained. Results indicated that communication instruction improves the critical thinking ability of the participants (longitudinal designs r = .176, cross-sectional designs r = .196). Forensic participation demonstrated the largest positive impact on critical thinking improvement, but all communication skill experiences demonstrate significant improvement. The cumulative evidence indicated that communication skill instruction generates, using the Binomial Effect Size Display (BESD), a 44% increase in critical thinking ability. This summary of available research provides documentation supporting the claims of departments and educators for the viability of communication skill instruction as a means of improving critical thinking. These results provide important evidence to support the maintenance of forensics programs in an era of increased educational accountability, downsizing, and budgetary cutbacks. (Contains 5 tables of data and 39 references.) (Author/NKA)