Contact lenses play an important role in the therapyTherapy of corneal diseases. They can be used as bandage lensesBandage lens for pain relief and support corneal wound healing. Iris lensesIris lens protect the eyeEye from too much glare and enhance the cosmetic situation, especially in an injured eyeEye. Regarding the treatmentTreatment of keratoconusKeratoconus, contact lenses represent the first step to improve visual acuity. This chapter describes how successful modern contact lens therapy can be and how special contact lens designs are manufactured with the help of different topographic analysis of the cornea. The most common specific contact lenses, used in keratoconusKeratoconus contact lens fitting, are presented. Contact lenses also play a crucial part for visual rehabilitation after keratoplasty. The differing geometries of the corneaCornea after suture removalSuture removal also require individual solutions. Due to the use of high-oxygen-permeable materialsHigh-oxygen-permeable material, we have almost unlimited possibilities for fittings with several designs: special rigidSpecial rigid gas permeable keratoconus lens keratoconusKeratoconus lenses, individual topographicallyIndividual topographic calculated custom-made contact lens calculated contact lenses, semi-scleralSemi-scleral contact lens and scleral contact lensesScleral contact lens. The latter enable new possibilities in contact lens fitting after keratoplastyKeratoplasty, too. All these types of contact lenses, such as special softSoft gas permeable (GP) keratoconus contact lens keratoconus contact lenses, hybrid contact lensesHybrid contact lens and “piggybackPiggyback contact lens system” contact lens systems, are shown including fitting examples.