BACKGROUND The truncated cone overall geometry of the native aortic root, an important factor in maintaining valvular competence, is significantly altered in cases of root aneurysms. We hypothesized that an early trial restoration of valve competence within the native aortic root followed by in situ three-dimensional measurements may lead to a more predictable functional reconstruction. METHODS The operation started with downsizing annuloplasty followed by sinotubular junction plication until full valve competence was observed and tested with the saline squirt test. Subsequent measurements (basal ring and sinotubular junction size, the depth of each sinus of Valsalva) formed the basis of graft sizing and tailoring. Reconstruction was completed with a new proximal suture line technique combining David subannular pledgeted fixation with Yacoub remodeling. RESULTS Ten patients were operated on during a 3-year period. Intraoperative (nonpressurized) competence by open testing translated into good postoperative valve function seen on transesophageal echocardiography. In situ measurements were done in the last 7 patients, and in 5 of them the restored root geometry was of a reverse cone (sinotubular junction 2 to 4 mm larger than basal ring size). CONCLUSIONS Rebuilding the aortic root based on in situ measurements with a fully competent aortic valve is a conceptually new surgical approach. Our observations suggest that postoperative valve competence, particularly with elongated valve leaflets, may not depend on the normal truncated cone geometry.