Personal and Professional Development (PPD) is now key to the undergraduate medical curriculum and requires provision of appropriate learning experiences. In order to achieve this, it is essential that we ascertain students' perceptions of what is important in their PPD. We required a methodological approach suitable for a large medical school, which defines constructs used by the students to describe their PPD, and is not constrained by a researcher's predetermined line of questioning. It should also quantify the saliencies of these constructs in the student population and indicate how they gauge their own PPD. The instrument should also be suitable for administration at key stages of the students' learning experience. Here we describe the first stages in developing a novel method, which fulfils these requirements. It is based on a modified self repertory grid, the "Ideal Self" Inventory. All first year students (N = 379), provided five descriptors of a "good medical student" and of a not very good medical student, which generated 1,531 'ideal' qualities. To define underlying themed constructs, 49 randomly selected descriptors, were grouped together by self selected students (n = 55), using commonly held assumptions. Frequency of item co-occurrence was tabulated by multidimensional scaling. Themed clusters of 'ideal' qualities, defined by hierarchical cluster analysis, were overlaid onto the multidimensional scaling to generate a concept map. This revealed seven themed constructs; Personal Welfare, Time and Self Management Committed Work Ethic, Learning Skills, Personal Development/Reflection, Personal and Professional Conduct and Teamwork. We then analysed the 1,531 'ideal' qualities, by determining the frequency with which students used each construct and the proportion of students who used a construct at least once. Personal and Professional Conduct, Committed Work Ethic and Time and Self Management were the most frequently used, implying that they were the most salient for the first year students.