Martin and Company, also known as Karlton's, Fishgalls & Cameo, is a historic building located in Sioux City, Iowa, United States.

The three-story building completed in 1902 features Beaux-Arts styling that includes a roof-line knee wall, and a cornice with acanthus leaf brackets and decorative swags.

In 1911 they hired yet another local architect, William L. Steele, to design a completely new facade to unify 515–517, 519 and 521 Fourth Street.

Martin and Company moved into a new six-story building across Nebraska Street, no longer extant, in 1919 this facility was divided into multiple storefronts and occupied by a variety of commercial enterprises.

The 515-517 portion of the Fourth Street facade was covered with a wood face and its cornice removed, before it was significantly altered to its present appearance.