PURPOSE: To compare external levator advancement and Mü ller’ s muscle-conjunctival resection (conjunctivomuller-ectomy, or CJM) for correction of upper eyelid involutional ptosis. DESIGN: Retrospective, nonrandomized, comparative interventional case series.METHODS: Reviewofmedical records of 159 patients (272 surgical procedures)who underwent external levator advancement or CJMwas performed. main outcome measures: Functional and cosmetic outcome, marginal reflex distance one (MRD1), and surgical complications. RESULTS: A total of 159 patients (51 men, 108 women, mean age 70 years) underwent 272 surgical procedures for upper eyelid ptosis; concurrent blepharoplasty was performed in 141 cases. MRD1 increased an average of 1.6 (± 1.5) mm, from 0.8 mm (± 1.2) preoperatively to 2.3 mm (± 1.2) postoperatively (P < .001). Fifteen patients (5.5% ) underwent reoperation for residual ptosis, nine (18% ) in the external levator advancement group, two (3% ) in the CJM group, three (8% ) in the external plus blepharoplasty group, and one (1% ) in the CJM plus blepharoplasty group (P< .001). Patients who underwent external levator advancement had significantly more severe ptosis preoperatively but attained similar eyelid position postoperatively as compared with CJM patients. Complications included overcorrection in four cases (1.4% ), lagophthalmos of 1 mm in 10 (3.6% ), and pyogenic granuloma in two ( < 1% ). CONCLUSIONS: External levator advancement and CJM performed alone or with concurrent blepharoplasty are effective treatments for upper eyelid ptosis. Residual ptosis or postoperative eyelid retraction occurs in up to 20% of cases and can be addressed successfully with a second operation. PURPOSE: To compare external levator advancement and Mü ller ’s muscle-conjunctival resection (conjunctivomuller-ectomy, or CJM) for correction of upper eyelid involutional ptosis. DESIGN: Retrospective, nonrandomized, comparative interventional case series. METHODS: Review of medical records of 159 patients (272 surgical procedures) who underwent external levator advancement or CJM was performed. Main outcome measures: Functional and cosmetic outcome, marginal reflex distance one (MRD1), and surgical complications. RESULTS: A total of 159 patients age 70 years) underwent 272 surgical procedures for upper eyelid ptosis; concurrent blepharoplasty was performed in 141. MRD1 increased an average of 1.6 (± 1.5) mm, from 0.8 mm (± 1.2) preoperatively to 2.3 mm (± 1.2) postoperatively ( Fifteen patients (5.5%) underwent reoperation for residual ptosis, nine (18%) in the external levator advancement group, two (3%) in the CJM group, three (8%) in the external plus blepharoplasty group, and one (1%) in the CJM plus blepharoplasty group (P <.001). Patients who underwent external levator advancement had significantly more severe severe ptosis preoperatively but attained similar eyelid position postoperatively as compared with CJM patients. CONCLUSIONS: External levator advancement and CJM performed alone or with concurrent blepharoplasty are effective treatments for upper eyelid ptosis. Residual ptosis or postoperative eyelid retraction occurs in up to 20% of cases and can be addressed successfully with a second operation.