Fifty-nine second-year medical students were asked to solve 12 Piagetian formal operational tasks. The purpose was to describe the formal logical characteristics of this medical student sample (59 of a total 65 possible) in terms of their abilities to solve problems in four formal logical schemata-combinatorial logic, probabilistic reasoning, propositional logic, and proportional reasoning. These tasks were presented as videotape demonstrations or in written form, depending on whether or not equipment manipulation was required, and were scored using conventional, prespecified scoring criteria. The results of this study show approximately 96% of the sample function at the transitional (Piaget's 3A level) stage of formal operations on all tasks and approximately 4% function at the full formal (Piaget's 3B level) stage of formal operations on all tasks. This sample demonstrates formal level thinking to a much greater degree than other samples reported in the literature to date and suggests these students are adequately prepared and developed to meet the challenge of their training (i.e., medical problem solving).