Blepharitis is a chronic condition and full recovery is difficult to achieve. It requires good patient compliance and an individual treatment regime. There are many conditions which can cause blepharitis, and it is essential to find the cause to give the proper treatment. There is scarce evidence for the recommended guidelines. Blepharitis itself rarely causes vision loss, but in case of complications like keratitis it is more frequently observed. When patients do not respond to the treatment it is important to consider if it is caused by immunological diseases or carcinoma, as argued in this review.