A prospective, single-center study was conducted to investigate the effectiveness and lasting effect of full-time occlusion therapy in treating amblyopia in 11- to 15-year-old children. Fifty-five compliant children who had amblyopia as a result of strabismus, anisometropia, or both, were treated with full-time (during all waking hours) occlusion of their good eye until no further improvement in the visual acuity of the amblyopic eye was observed on 3 consecutive monthly follow-up examinations. After this, part-time (4 hours per day) occlusion therapy was used randomly in 24 of 55 patients for 3 to 6 months for maintenance of the final visual acuity. All 55 patients had improved visual acuity after treatment. The mean improvement was 0.46 ± 0.24 logMAR unit (4.6 Snellen lines) which was statistically significant (P < .0001). Maximum improvement was 0.90 logMAR unit (9 Snellen lines) in 2 patients. Patient age had no significant effect on mean improvement in visual acuity, although patients 14 to 15 years old showed a statistically significantly late improvement compared to those 11 years old (P < .05). There was no change in the visual acuity of the good eyes. Thirty-two of the patients had a mean follow-up of 17.6 months after the cessation of full-time and maintenance occlusion therapy. Twenty-nine (91%) of the 32 patients maintained improved visual acuity, while 3 (9%) exhibited a regression in visual acuity. Maintenance occlusion therapy did not have a significant stabilizing impact on the improved visual acuity. The conclusion was that compliant, full-time occlusion effectively improves acuity in children 11 to 15 years old with amblyopia and that lasting effects can be achieved, with or without maintenance patching.—Michael D. Wagoner A prospective, single-center study was conducted to investigate the effectiveness and lasting effect of full-time occlusion therapy in treating amblyopia in 11- to 15-year-old children. Fifty-five compliant children who had amblyopia as a result of strabismus, anisometropia, or both, were treated with full-time (during all waking hours) occlusion of their good eye until no further improvement in the visual acuity of the amblyopic eye was observed on 3 consecutive monthly follow-up examinations. After this, part-time (4 hours per day) occlusion therapy was used randomly in 24 of 55 patients for 3 to 6 months for maintenance of the final visual acuity. All 55 patients had improved visual acuity after treatment. The mean improvement was 0.46 ± 0.24 logMAR unit (4.6 Snellen lines) which was statistically significant (P < .0001). Maximum improvement was 0.90 logMAR unit (9 Snellen lines) in 2 patients. Patient age had no significant effect on mean improvement in visual acuity, although patients 14 to 15 years old showed a statistically significantly late improvement compared to those 11 years old (P < .05). There was no change in the visual acuity of the good eyes. Thirty-two of the patients had a mean follow-up of 17.6 months after the cessation of full-time and maintenance occlusion therapy. Twenty-nine (91%) of the 32 patients maintained improved visual acuity, while 3 (9%) exhibited a regression in visual acuity. Maintenance occlusion therapy did not have a significant stabilizing impact on the improved visual acuity. The conclusion was that compliant, full-time occlusion effectively improves acuity in children 11 to 15 years old with amblyopia and that lasting effects can be achieved, with or without maintenance patching.—Michael D. Wagoner