Background: Hospitalization can expose patients to numerous adverse events associated with their care. To make health care professionals aware of these events, medication errors were simulated using the "room of errors" model. Objectives: To describe the methods of implementing a "room of errors" and to evaluate participants' performance in identifying errors. Methodology: This cross-sectional descriptive simulation study was carried out in the experimental pharmacy of a faculty of pharmacy over 2 days in December 2021 and January 2022. The study involved pharmacy interns and residents at various stages of their internships. Results: Thirty-six interns and 8 residents participated in the "room of errors" workshop. The overall correct response rate was 70.8% (n = 269/380). The error detection rate was 45.3% for pharmacy interns and 57.5% for residents, although this difference was not statistically significant. Certain hazards were identified by the majority of students (soiled compress on the treatment trolley, prescription of acetaminophen to a patient with an allergy to this drug), whereas others were rarely identified (a box containing food in the refrigerator, an empty bottle for hand sanitizer). Respondents to the satisfaction survey mainly considered this workshop to be a useful educational tool and would like to see this type of workshop integrated into their training. Conclusion: The "room of errors" seems to be an effective way of raising awareness about the risks associated with hospitalization and patient safety. This type of tool should be integrated into education and training programs.