BACKGROUND: The foundations of an effective and evidence-based training program are the metrics, which characterize optimal performance. PURPOSES: To develop, operationally define, and seek consensus from procedure experts on the metrics that best characterize a reference approach to the performance of a closed reduction and internal fixation of a 31A2 unstable pertrochanteric fracture with a cephalomedullary nail with distal locking through the proximal guide. METHODS: A Metrics Group consisting of 3 senior orthopaedic surgeons, a surgeon/medical scientist, an education expert and a behavioural scientist deconstructed the performance of the selected fixation procedure and defined performance metrics. At a modified Delphi meeting, 32 senior orthopaedic and trauma surgeons from 18 countries critiqued these metrics and their operational definitions before reaching consensus. RESULTS: Initially performance metrics consisting of 14 Phases with 62 Steps, 84 errors and 20 Sentinel errors were identified that characterize the safe and effective performance of the procedure. During the Delphi panel meeting these were modified and consensus was reached on 15 Phases (1 added, p = 0.967)) with 75 Steps (14 added and 1 deleted; p = 0.028), 88 errors (10 added and 6 deleted; p = 0.47), and 28 Sentinel errors (8 added; p = 0.107). Pre and Post Delphi characterizations were highly correlated (r = 0.81-0.94). CONCLUSIONS: Surgical procedures can be broken down into constituent, essential, and elemental tasks necessary for the safe and effective completion of a reference approach to a specified procedure. Procedure experts from 18 countries reached consensus on performance metrics for the fixation procedure. This metric-based characterization should form the basis of more quantitative validation studies to guide the construction of a proficiency-based progression training curriculum.