PURPOSE: Dacryocystorhinostomy (DCR) is the standard procedure for the treatment of acquired nasolacrimal duct obstruction (NLDO) that can be performed through an external or endonasal approach. Both techniques create a fistula from the lacrimal sac into the nasal cavity via a bony osteotomy. Historically, external DCR has been considered the gold standard; however, recent reports suggest endonasal DCR is an effective alternative. There are numerous variations of endonasal DCR described in the literature that report variable success rates. The purpose of this study is to describe the approach and success rate with endonasal DCR in which nasal mucosa, bone, and lacrimal sac mucosa are sequentially removed. METHODS: The authors retrospectively reviewed cases of endonasal DCR from 2004 to 2011 from 2 institutions (the University of California, San Diego, California, and the Fante Eye and Face Center in Denver, Colorado, U.S.A.). Patients with a history of epiphora and NLDO confirmed with punctal irrigation were included. Exclusion criteria were the presence of canalicular obstruction, history of orbital trauma, and prior DCR surgery. Success was defined as subjective relief of epiphora and confirmation of ostium patency with irrigation. RESULTS: A total of 324 patients (74 men, 250 women; mean age 59.3) encompassing 407 endonasal DCR cases were included in the study. The total case success rate was 92.2% with an average follow-up time of 91.5 days. Revision surgery was performed in 7 of the failed cases and resulted in success in 6 of these cases. CONCLUSIONS: Endonasal DCR is a simple and effective approach to surgically treat NLDO and offers success rates comparable with external DCR.