Over the past 2 decades, the operative experience of surgical residents has undergone major changes due to advances in the science and technology of surgery, treatment modality, growth of subspecialties, work hour regulations, and an emphasis on shorter hospitalization. Method: We performed a comprehensive statistical analysis of national data from ACGME (1998-2008), with a focus on changes in the component operations. Results: Since 1993, when minimally invasive surgery was first recorded in ACGME data base, the US residents' open operative experience began 10 register a continuing decline, Today, a quarter of the resident's,operations are closed procedures. During the same period, trauma operative experience has decreased by 50%. If the decline in open operations continues at this rate, within 10 years it will drop to less than 60% of that in 1993. Gastrointestinal (especially biliary) operations are the most affected. Changes in ACGME data format of component operations made it difficult to determine the effect of work hour limit by looking at total operations alone. Conclusion: Training in open operative surgery, the foundation of the craft of surgery, is oil the decline. Lack of operative trauma hurts intra-operative crisis management and decision making. These deficiencies deserve educational effort at a higher priority than accorded so far.