This is a descriptive report of a course unit designed to introduce co
ncepts of medical problem-solving during the first month of an undergr
aduate MD curriculum. The unit is also used to provide an introduction
to the dynamics of cooperative small group learning. The value of the
unit was endorsed by the subjective opinions of faculty tutors and st
udents, who recognized the relevance of the unit to the clinical pract
ice of doctors. An end-of-course examination demonstrated that some no
vice medical problem-solvers have difficulty with recursive hypothesis
testing and tend to use linear strategies. This type of learning expe
rience has the potential to identify students who may have subsequent
difficulty in clinical reasoning tasks in the curriculum. Medical prob
lem-solving itself is the primary focus of problem-based learning in t
he unit. Experience with this unit suggests that concepts of medical p
roblem-solving can be introduced into the curriculum at a very early s
tage, without a prerequisite for substantial knowledge of medical scie
nces.