This study examined the perceptions of basic education school teachers in Turkey to the educational software evaluation criteria, developed for the acquisition of multimedia instructional software by the Turkish Ministry of National Education, from the viewpoint of actual users. Data were collected through structured interviews, group discussions, and participant observation. The findings indicate that instructional adequacy is the most important criterion both from the theoretical and from the practical perspective; a second factor mentioned was that effective instructional software should include real-life examples and simulations of abstract concepts. Criteria considered as having secondary importance were the variety and number of exercises, the aspect of developing students' creativity and critical thinking capacity, presentation of accurate information, being free from scientific errors, individualizing learning, being in accordance with the pedagogical level of students, and being enriched through the use of a variety of sound effects, images, videos, and animations. Other questions addressed the conditions under which instructional software was used and issues to be taken into consideration in the future phases of instructional software procurement and technology assisted instruction. (Contains 11 references.) (MES)