This study explored how regular teachers (N=20) and special education teachers (N=20) think and make instructional decisions about special needs students. Teachers viewed a videotape of a reading comprehension lesson for a small group of third grade students. One student was a target for observation and classified as learning disabled. Quantitative and qualitative procedures were used to analyze teacher response to two measures, one a structured measure where teachers rated the importance of instructional variables for the student and one an unstructured measure requesting teachers to make instructional recommendations for the student. Findings suggest that regular and special teacher groups may have developed different professional knowledge structures from which to interpret classroom events, identify and solve instructional problems, and collaborate with each other. Six tables and a list of 44 references complete the document. (Author/LL)