The effectiveness of simulation is rarely evaluated. The aim of this study was to assess the impact of a short training course on the ability of anesthesiology residents to comply with current difficult airway management guidelines. Twenty-seven third-year anesthesiology residents were assessed on a simulator in a "can't intubate, can't ventilate" scenario before the training (the pretest) and then randomly 3, 6, or 12 months after training (the posttest). The scenario was built so that the resident was prompted to perform a cricothyrotomy. Compliance with airway management guidelines and the cricothyrotomy's duration and technical quality were assessed as a checklist score [0 to 10] and a global rating scale [7 to 35]. After training, all 27 residents (100%) complied with the airway management guidelines, compared with 17 (63%) in the pretest (P < 0.005). In the pretest and the 3-, 6-, and 12-month posttests, the median [range] duration of cricothyrotomy was respectively 117 s [70 to 184], 69 s [43 to 97], 52 s [43 to 76], and 62 s [43 to 74] (P < 0.0001 vs. in the pretest), the median [range] checklist score was 3 [0 to 7], 10 [8 to 10], 9 [6 to 10], and 9 [4 to 10] (P < 0.0001 vs. in the pretest) and the median [range] global rating scale was 12 [7 to 22], 30 [20 to 35], 33 [23 to 35], and 31 [18 to 33] (P < 0.0001 vs. in the pretest). There were no significant differences between performance levels achieved in the 3-, 6-, and 12-month posttests. The training session significantly improved the residents' compliance with guidelines and their performance of cricothyrotomy.