Purpose. To assess medical students' perceptions of the ethical enviro
nment across four years of medical school. Method. In the spring of 19
96, the authors distributed a questionnaire to all four classes at the
Wake Forest University School of Medicine. The students provided demo
graphic information and information about their exposures to or partic
ipation in unethical situations. Results were analyzed using multiple
analysis of variance, univariate analysis of variance, Pearson correla
tion, and cross-tabulations. Results. The response rate was 71%. The s
tudents reported that exposures to unethical behavior started early an
d continued to increase with each year in school. For example, 35% of
the first-year students reported observing unethical conduct by reside
nts or attending physicians. This percentage rose to 90% of the fourth
-year students. The authors found no significant relationship between
demographic variables other than the year in school and the ethical di
lemma variables. Conclusion. Medical students face perceived ethical d
ilemmas beginning as early as the first year of medical school. Thus e
thics instruction must; begin in the freshman year. In addition, there
must be changes to the environment in which clinical education is con
ducted to enhance the positive enculturation of students into the medi
cal profession.