This paper reports on the results of three different investigations into pre-service teachers' understanding of the mathematical concepts of area and perimeter. Different test instruments were used with three cohorts from two universities in order to identify pre-service teachers' understandings and common misconceptions. The results indicated that many pre-service teachers across the cohorts had a procedural understanding of area and perimeter, displayed similar misconceptions to their student counterparts, and were limited in their ability to demonstrate examples of the mathematics knowledge required to teach these topics. The findings add to the limited field of research into primary pre-service teachers' understanding of area and perimeter, particularly within an Australian context and across institutions.