Students who enter college with a solid grounding in, and positive attitudes toward, evolutionary science are better prepared for and achieve at higher levels in university-level biology courses. We found highly significant, positive relationships between student knowledge of evolution and attitudes toward evolution, as well as between introductory biology course achievement and both precourse acceptance of evolution and precourse knowledge of evolution, among students at a medium-sized private northeastern university. Teachers who scant the teaching of evolution or who do not foster good attitudes toward evolution are compromising their students' potential for success in science at the college level.