Assessing surgical trainee operative performance is time- and resource-intensive. To maximize the utility of each assessment, it is important to understand which assessment activities provide the most information about a trainee's performance. The objective of this study is to identify the procedures that best differentiate performance for each general surgery postgraduate year (PGY)-level, leading to recommendations for targeted assessment. The Society for Improving Medical Professional Learning (SIMPL) operative performance ratings were modeled using a multilevel Rasch model which identified the highest and lowest performing trainees for each PGY-level. For each procedure within each PGY-level, a procedural performance discrimination index was calculated by subtracting the proportion of "practice-ready" ratings of the lowest performing trainees from the proportion of "practice-ready" ratings of the highest performing trainees. Four-quadrant plots were created using the median procedure volume and median discrimination index for each PGY-level. All procedures within the upper right quadrant were considered "highly differentiating, high volume" procedures. This study was conducted across 70 general surgical residency programs who are members of the SIMPL collaborative. A total of 54,790 operative performance evaluations of categorical general surgery trainees were collected between 2015 and 2021. Trainees who had at least 1 procedure in common were included. Procedures with less than 25 evaluations per training year were excluded. The total number of evaluations per procedure ranged from 25 to 2,131. Discrimination values were generated for 51 (PGY1), 54 (PGY2), 92 (PGY3), 105 (PGY4), and 103 (PGY5) procedures. Using the above criteria, a total of 12 (PGY1), 15 (PGY2), 22 (PGY3), 21 (PGY4), and 28 (PGY5) procedures were identified as highly differentiating, high volume procedures. Our study draws on national data to identify procedures which are most useful in differentiating trainee operative performance at each PGY-level. This list of procedures can be used to guide targeted assessment and improve assessment efficiency.