Shure was founded by Sidney N. Shure in 1925 as “The Shure Radio Company”, selling radio parts kits several years after completely manufactured radios became commercially available. The company’s office was located at 19 South Wells Street in downtown Chicago, Illinois. The following year, Shure published its first direct mail catalog, which was one of only six radio parts catalogs in the United States at the time. By 1928, the company had grown to over 75 employees, and Sidney’s brother, Samuel J. Shure, joined the company, which was renamed Shure Brothers Company. The company moved into new offices at 335 West Madison Street in Chicago. In 1929, with the advent of the Great Depression and the increased availability of factory-built radios, Shure Brothers Company was forced to greatly reduce their staff and became the exclusive US distributor of a small microphone manufacturer. In 1930, Samuel J. Shure left the company.

In 1931, Shure and engineer Ralph Glover began development of the first Shure microphone, and the following year, the Model 33N Two-Button Carbon Microphone was introduced, making Shure one of only four microphone manufacturers in the U.S. Shure’s first condenser microphone, crystal microphone, and microphone suspension support system (for which they received their first patent) were all introduced that same decade. In 1939, Shure introduced the Model 55 Unidyne Microphone, which went on to become one of the world’s most recognized microphones.