Conical cornea is an eye disease characterized by a dilated cornea with a thinning and softening of the center protruding forward in a conical shape. It often results in high levels of irregular myopic astigmatism. In advanced stages, acute corneal edema, scarring, and significant loss of vision may occur, at which point patients require corneal transplantation. Corneal collagen cross-linking is available for some patients in the early and intermediate stages of the disease. Corneal cross-linking is a novel treatment to increase the mechanical stability of corneal tissue. The aim of the treatment is to create new chemical bonds within the corneal stroma through highly confined photochemical polymerization. The current indications for cross-linking therapy are diseases in the category of corneal bulging, such as conical corneas, clear limbal corneal degeneration, medically induced corneal bulging after refractive surgery, and various types of corneal melts for which conventional treatments are ineffective, and more than 30,000 patients worldwide have received cross-linking therapy. The technology was developed by Prof. Theo Seiler and Prof. Eberhard Spoerl at the University of Dresden, Germany, between 1993 and 1997. It was first applied to patients in 1998. Today corneal cross-linking is performed in more than 300 medical centers worldwide. Photochemical polymerization using ultraviolet light has been found to be the most promising technique for achieving cross-linking in connective tissue. A non-toxic, soluble photomediator activates photochemical polymerization and it absorbs light waves of a certain wavelength sufficiently to protect the deep ocular tissues (Riboflavin-UVA technology). As a result, progressive corneal softening and thinning gradually slows down or even stops, and the biomechanical strength of the corneal tissue can be significantly increased. To date, more than 30,000 affected eyes worldwide have been treated with crosslinking and have been followed up for more than 5 years. Clinical studies have shown that in more than 85% of the eyes, the progression of the lesion is controlled, the rate of progression decreases, and in a few patients, the visual acuity with lenses improves. After 6 months of corneal cross-linking treatment, astigmatism was reduced in more than 80% of affected eyes. The steepest K-value is typically reduced by 1D, and the actual clinical reduction is more than 86% of eyes. Corneal cross-linking is a safe treatment if recommended safety guidelines are followed. Therefore, the potential risks can be greatly minimized by having a formal examination prior to treatment, with all parameters complying with the safety guidelines. Cross-linking may become the standard of care in the treatment of conical corneas, thereby slowing the progression of the disease!