Objectives: Since 1998, the volume of open abdominal aortic aneurysm (AAA) repairs (OAR) has decreased to just 7% of all AAA repairs. This is due to an increase in endovascular AAA repair (EVAR) and advanced methods such as fenestrated (FEVAR) and branched (BrEVAR) repairs. Projected trends in AAA repair techniques over the next 5 years will impact training, regionalization of care, hospital preparedness, and individual practice patterns.Methods: National and State Inpatient Databases were utilized between 1998 and 2012 to determine AAA trends and method of repair in conjunction with industry sources through 2014. The volume of OAR, EVAR, FEVAR, and BrEVAR for all patients with AAA were determined and projections created through the use of S-curve modeling, sensitivity analysis, and forecasting through 2020. Outcome measures included length of stay, complications, readmissions, inpatient mortality, and cost of care.Results: A total of 42,213 elective OAR cases were completed in 1998. With the introduction of EVAR, OAR cases declined to 11,428 by 2010. Nationwide, all but six states still completed an average of five or more OAR cases per individual practitioner in 2010. However, with the introduction of FEVAR and BrEVAR, along with the continuing rise in EVAR volume, only 13 states still completed more than five OAR cases by 2015. Less than 1% of practitioners are expected to complete more than five OAR cases per year by 2020. This decline in volume is associated with an increase in length of stay, perioperative complications, readmission to the hospital, inpatient mortality, and cost of care (P < .001 for each variable; R 2 ¼ 0.87-0.98).Conclusions: By 2020, only a small minority of practitioners will complete OAR in sufficient volume to minimize adverse effects on patients. Further, most practitioners will complete fewer than one elective OAR per year by this time. However, endovascular repair for ruptured AAA has not yet had the same penetration as for elective cases. The declining experience with OAR may significantly impact patient outcomes over the next 5 years for both elective and ruptured AAA patients. This may prompt regionalization, hospital preparedness, and changes in individual practice patterns that may adversely impact the field of vascular surgery.