Markus Ritzmann gained his expertise in contact lens fitting in the last 10 yrs. Substantially while working as consultant at Falco Linsen AG, Switzerland, a specialty lens manufacuter. He established the Linsencentrum, Falco's in house specialty lens clinic (www.linsencentrum.ch).In 2012 he started his Masters degree extra-occupational at Aalen University, Germany. The clinical optometry program colaborates with NECO (New Endland Collage of Optometry, Boston, MA) and Pacific University (Forest Grove, OR). In 2015 he finished his degree MSc. Vision Science and Business and won the Karl Amon Optometry Award for on of the two best Master Thesisis. After his degree he continued his research in the area of scleral lenses and the shape of the anterior sclera with Patrick Caroline from Pacific University. Their research is published in the CLAE Journal (https://doi.org/10.1016/j.clae.2017.10.010).The core work at Linsencentrum is specialty lens fitting with patients who have Keratokone, Post Surgery (Keratoplasties, Laser, Keratotomy,...), Post-traumatic eyes with irregular ocular surface, severe drye eyes, aniridia and irisdefects, prosthetics...Alongside he fits regular patients with myopia, hyperopia, astigmatism and presbyopia with diverse bifocal- or multifocal contactlenses. Ortho-Keratology in regular Patients and Myopia control in children is another specialty field.