Introduction: First generation drug-eluting stents (DES), such as sirolimus-eluting Cypher or paclitaxel-eluting Taxus stent, reduce neointimal hyperplasia markedly and thus restenosis rate, but prevent stented segements from being covered by endothelium. Complex lesions such as long lesions or bifurcation lesions often require two or more stents with stent overlapping and may be one of causes of poor healing and consequently, stent thrombosis. Endeavor stent, one of the 2nd generation DES, has biocompatible polymer, which is known to interfere endothelial coverage minimally and may be safer in the setting of overlapping stents. Methods: From June 2007 to August 2008, 201 patients undergoing percutaneous coronary intervention for bifurcation lesion or long diffuse lesion requiring stent overlapping were enrolled in a prospective open label multicenter registry, in which 5 hospitals in South Korea participated. Stent selection was decided by operator's choice, but it was recommended that the ratio of Endeavor stent versus 1st generation DES's (Cypher or Taxus) be 3:1. Two-year clinical follow up and 9-month angiographic follow up were done. Results: Of 201 patients 140 (69.7%) had Endeavor stents and 61 (30.3%) non-Endeavor 1st generation stents (51 (25.4%) Taxus, 10 (5.0%) Cypher). Two-year follow up rate was 93.5%. Total major adverse cardiovascular event (death, nonfatal myocardial infarction, stroke, and target vessel failure), as the primary end point, occurred 19 (13.7%) in Endeavor group and 12 (19.7%) in non-Endeavor group (p=NS). For bifurcation lesions (77 patients), total MACE occurred in 4 patients (7.3%) and 6 (27.3%) in Endeavor group (55 patients) and non-Endeavor group (22), respectively, and showed statistical significance (p=0.025). Total mortality was 1.8% (1 patients) vs 13.6% (3) in Endeavor vs. non-Endeavor group, respectively (p=0.035). Conclusion: For bifurcation lesion, Endeavor stent showed statistically lower MACE and total mortality than 1st generation DES's. Second-generation DES like Endeavor stent may be safer in the complex lesions like bifurcation lesion than 1st generation DES's.