Background: There is no agreed system that is acknowledged as the ideal assessment of laparoscopic operative and cognitive skills. A new approach that combines Objective Structured Clinical Examination (OSCE) and Observational Clinical Human Reliability Assessment (OCHRA) was developed and used to assess trainees' operative and cognitive skills during laparoscopic training courses. Methods: Performance of 60 trainees participating in 3-day essential laparoscopic skills training (cognitive and psychomotor) courses were assessed and scored using both OSCE and OCHRA. Results: The study showed significant inverse correlations between the number of technical errors identified by OCHRA and the scores obtained by OSCE for individual tasks performed either by electro-surgical hook or laparoscopic scissors (r = -0.864 and r = -0.808, respectively). Significant differences between trainees were observed in relation to both overall OSCE scores and OCHRA parameters: execution time, total errors, and consequential errors (P < 0.001). Conclusions: OCHRA provides a discriminative feedback assessment of laparoscopic operative skills. OCHRA and OSCE are best regarded as complementary assessment tools for operative and cognitive skills. The present study has documented significant variance between surgical trainees in the acquisition of both cognitive and operative skills.