Problem-based learning (PBL) is now an established method in undergraduate medical education that aims to develop reasoning skills based on clinical problems. More recently, the use of concept mapping in medical education aims to improve meaningful learning. At the New University of Lisbon, we have been using PBL as a major educational method in a pathophysiology course. In 2003 - 2004, we started to use Inspiration, a computer-based concept mapping tool, with a single tutorial PBL group. A total of 36 maps were constructed related to short cases, already used in the PBL course, in which a certain number of key nodes were hidden to allow the students to fill in the gaps. The results obtained appear to indicate that the use of concept maps stimulated meaningful learning within a PBL course.