Common characteristics in the theory and process of two instructional models, one in critical thinking skills and one in library skills, were isolated in this study. Content analysis of selected materials from Robert H. Ennis's critical thinking model and Carol C. Kuhlthau's library skills model showed the absence or presence of common characteristics as well as the frequency of occurrence. Of the 72 process model characteristics analysed, 55 were present in both models of instruction. Of these characteristics, eight occurred with the most frequency in both the critical thinking model and the library skills model. Common characteristics emphasized the process nature of both theoretical bases. In the analysis of both process bases, the common characteristics pointed to the nature of thinking as focused and purposive, intentional about the process, and reflective. Another common characteristic was that the process required evaluation of information. The remaining common characteristic suggested the use of constructed response tests (essays or term papers). The commonalities linking both models appear to support a process approach to instruction, as well as a metacognitive view of the thinking process. Appended are a list of materials and the coding sheet used in the content analysis. (Contains 24 references.) (KRN)