This study investigated effects of a Direct Instruction reading comprehension program implemented with students with autism spectrum disorders (ASD) and developmental disabilities (DD). There is little research in the area of reading comprehension for students with ASD and no research as to the effectiveness of reading comprehension Direct Instruction (DI). This study extended previous research by investigating the extent to which more complex instruction could be implemented with students with ASD and DD and its effect on their reading comprehension. A multiple probe across behaviors design was used. A functional relation between Direct Instruction and reading comprehension skills and behaviors was demonstrated across all behavioral conditions and across students. Data were also collected using curriculum-based assessments and all student demonstrated improvement. Results and their implications are discussed further. (Contains 1 table and 4 figures.)