Initially the training of MohsMohs surgeons involved shadowing Dr. Frederic E. MohsFrederic E. Mohs in Madison, WI, observing the in vivo fixative method and learning to heal the wounds by second intention. In 1967, Dr. MohsMohs founded the American College of ChemosurgeryChemosurgery, now known as the American College of Mohs Surgery (ACMSAmerican College of Mohs Surgery (ACMS)), which sought to foster education in science and clinical practice. After the fresh frozen tissueFresh frozen tissue method was introduced in the 1970s, the procedure achieved widespread acceptance by patients and physicians alike and the demand required a larger number of physicians to become trained in Dr. MohsMohs’ technique. The ACMSAmerican College of Mohs Surgery (ACMS) established criteria for formal fellowships in order to promote a high quality of education with academic rigor and the first approved fellowships in the USA began in the early 1980s with international fellowships being approved approximately 10–12 years later. New MohsMohs surgeons were also trained in reconstructive techniques and developed many aesthetic procedures. By 2007, at least 77 approved fellowships existed worldwide. The ACMSAmerican College of Mohs Surgery (ACMS) transferred approval and oversight gradually to the ACGMEAccreditation Council for Graduate Medical Education (ACGME) beginning in 2010. By the spring of 2011, 39 programs were approved by the ACMSAmerican College of Mohs Surgery (ACMS) and 44 by the ACGMEAccreditation Council for Graduate Medical Education (ACGME). In 2024, there were 4 international programs approved by the ACMSAmerican College of Mohs Surgery (ACMS) and 84 approved by the ACGMEAccreditation Council for Graduate Medical Education (ACGME) in the United States. The American Board of Dermatology (ABDAmerican Board of Dermatology (ABD)) conducted the first Board Certification examination in Micrographic Dermatologic Surgery (MDSMicrographic Dermatologic Surgery (MDS)) in 2021. This chapter details the evolution of the training and regulation of Mohs micrographic surgeryMohs micrographic surgery.