Participation in inservice training is one way in which teachers and other educational professionals learn and update the skills that they bring to the instructional process. Unfortunately, little descriptive or empirical research has been conducted that specifically examines the training professional who provides the training. This study had three main goals: to provide a window on the strategies that trainers use when they plan for workshop delivery; to examine the differences between expert and non-expert teacher trainers using an information processing perspective grounded in the research on cognitive psychology, expertise, and teaching; and finally, to provide an in-depth look at how expert trainers plan for workshops. The study had two parts. First, a workshop planning strategy questionnaire and demographic survey were administered to 78 training professionals attached to 16 federally funded regional training centers. Next, think aloud interviews were conducted with 3 trainers who had been identified as training experts by their peers. Exploratory data analyses revealed that trainers consider training expertise to be a function of three dimensions: knowledge of content, social affective skills and planning/organizational abilities. Exploratory analyses also showed that both experts and non-experts report using a wide variety of strategies when planning for workshops, although the least frequently reported strategies were rehearsal strategies (scripting and practicing what to say and do). Both experts and non-experts reported using strategies consistently in familiar and unfamiliar settings. A Kruskal-Wallis one-way ANOVA showed that were no significant differences between the groups of trainers in the reported use of metacognitive strategies. However, expert trainers report extensive metacognitive strategy use (particularly planning and self-monitoring strategies) during the think aloud interviews. Two additional Kruskal-Wallis ANOVAs revealed that neither previous coursework on teaching methodology and training nor previous classroom teaching experience (except at grades 4-5) showed any significant effects with respect to trainers’ categorization as experts. Experts, however, appear to be able to use their previous experiences and knowledge in a way which helps them become experts. The study concludes with implications for training development programs and implication for preparing and developing teacher trainers. / Ed. D.