The complications of blepharoplasty are infrequent, most often minor and transient, and rarely major and permanent with functional or aesthetic consequences. Treatment is above all preventive with screening of "at risk" patients in whom blepharoplasty would be contra-indicated. Patients must be informed of possible risks through informative booklets stressing the most important points. The complications may affect vision. Partial or complete visual loss due to ischemic optic neuropathy, or rarely to compression of the ocular globe by intraorbital hemorrhage, is the most serious complication. Other visual complications include oculomotor disorders, keratoconjunctivitis sicca, epiphora, and chemosis of lymphatic origin. Eyelid complications are more frequent: ptosis of the upper eyelid or lagophthalmia caused by incorrect resection of the skin, scarring, and eyelid fold anomalies. The most severe aesthetic complication is the malposition of the lower eyelid resulting in retraction, lagophthalmia, ectropion, deformation of the external canthus, or lower eyelid tissue relaxation. These malpositions are often minor, sometimes reversible, but they can be major, with psychological, aesthetic, and functional consequences. Other local complications include enophthalmia and hypo- or hypercorrection. General complications may include pigmentation anomalies or infections extending as far as the orbital fat tissue. Finally, complications observed after the newer procedures of laser surgery include ectropion, burns and residual redness. Complications related to periocular injections of filling material are also mentioned. The discussion of these complications is followed by a comprehensive review of the prevention, diagnosis and management of the complications after blepharoplasty.