Purpose: A multicenter, 2-visit, open-label, 4-week study was conducted to determine the acceptability of hydroxypropyl cellulose ophthalmic inserts in adult patients with a history of dry eye syndrome (DES)., Methods: At visit 1, patients (N = 520) were evaluated, screened by slit-lamp biomicroscopy, and completed the Ocular Surface Disease Index (OSDI), a validated measure of quality of life. Patients were trained in the proper placement and use of hydroxypropyl cellulose ophthalmic inserts and were contacted by telephone on day 3 of the study. At week 4, patients were given a clinical evaluation and completed a second questionnaire. Answers determined changes in symptoms and quality of life. Adverse events were monitored throughout the study., Results: Four hundred eighteen patients completed the study and reported significant improvements in discomfort, burning, dryness, grittiness, stinging, and light sensitivity (P = .05) after 4 weeks use of hydroxypropyl cellulose ophthalmic inserts. Significant improvements in clinical signs (keratitis, conjunctival staining, and tear volume) were reported. Contact lens wearers reported significant improvements similar to nonwearers, with a strong trend toward improvement in light sensitivity. Mean OSDI total scores, measuring quality of life, significantly improved by 21.3% (from 41.8 +/- 22.38 to 32.9 +/- 21.97, P < or = .0215). The most commonly reported adverse event leading to discontinuation was blurred vision, observed in 8.7% of patients (n = 45). Compliance during the study was good; 41.5% of subjects were fully compliant. Of the 58.5% of subjects who missed doses, the majority (69.4%) missed only one to five., Conclusions: Hydroxypropyl cellulose ophthalmic inserts significantly reduced symptoms and clinical signs of moderate to severe DES. They also significantly improved DES in patients wearing contact lenses. Patients experienced a statistically significant improvement in quality of life, as measured by the OSDI, of 21.3%.