Traditional practical classes in many countries are being rationalised to reduce costs. The challenge for university educators is to provide students with the opportunity to reinforce theoretical concepts by running something other than a traditional practical program. One alternative is to replace wet labs with comparable computer simulations. These virtual experiments involve no harm to animals and require little ongoing expenditure. This study documents second-year physiology students' perceptions of and attitudes to simulations by incorporating several computer simulations into the practical program. Computer simulations met the conceptual and, to some extent, the motivational goals of university practical programs. While students enjoyed both wet labs and computer-simulated exercises, overwhelmingly the wet lab provided the more memorable and stimulating learning experience. Based on this study, students suggested that computer simulations could be effectively used to complement rather than replace practical classes where students gain laboratory skills. (Contains 5 tables and 1 footnote.)