The success of school health programs depends upon effective communication. The characteristics of the communicator is an important component in the communication process. Research indicates that the expertise of the communicator and communicator-audience similarity are both characteristics that influence the acceptance of health information. The goal of this study was to determine which combination of expertise and similarity is most effective in improving the nutrition knowledge and attitudes of high school students in Kenya, East Africa. To examine this problem, Gusii students from Kenya received communications advocating improved nutrition from sources varying in expertise and similarity. Results of the investigation indicated that a communicator similar to his or her audience (low expert/high similar communicator) was effective in persuading the students as an expert (high expert/low similar communicator). The implications for school health programs, especially in developing countries, is that in utilizing a culturally similar, locally-trained person (low expert/high similar communicator) as a communicator source, the school is obtaining an effective communicator as well as utilizing limited resources in the most effective manner. If a culturally dissimilar person is the source of the information, then this individual would be effective only if he or she is an expert.