A substantial part of graduate education in veterinary medicine is spent in clinical practice. During the clinical experiential phase, it is difficult to monitor students' actual knowledge development: they build individual records of experiences based on the cases they have to deal with, while mainly focusing on knowledge that is of direct, clinical relevance to them. As a result, students' knowledge bases may differ to such a degree that a single test alone may not be able to provide an adequate reflection of progress made. In these circumstances, progress testing, which is a method of longitudinal assessment independent of the curricular structure, may offer a viable solution. The purpose of this study, therefore, was to determine the extent to which progress tests (PT) can be used to monitor progress in knowledge development at a graduate level in veterinary medical education. With a 6-month interval, we administered two tests to students based on the Maastricht Progress Test format that covered a large variety of veterinary topics. Consequently, we analyzed students' progress in knowledge development. Based on a substantive appraisal of the questions and analysis of the test results, we concluded that the tests met the measurement criteria. They appeared sensitive enough to gauge the progress made and were appreciated by the students. Hence, in spite of the differences within the whole graduate group, the PT format can be used to monitor students' knowledge development.