At age 17, Ireland was discovered by an agent for the Elite Model Management company, and by the time she graduated from San Marcos High School in Santa Barbara in 1981, she was working steadily as a model. She appeared on covers for Vogue, Cosmopolitan, Women's Fitness; and in campaigns for consumer products, including Bulova, Fruit of the Loom, Caress Soap, Budweiser, Cheerios, and Baked Lays Potato Chips.Starting in 1984, Ireland was featured in the annual Sports Illustrated Swimsuit Issue for 13 consecutive years, with her final appearance in 1996.In addition to her long tenure within the pages, Ireland appeared on the cover of the annual issue three times, a feat tied by Christie Brinkley and Cheryl Tiegs, and surpassed only by Elle Macpherson (with five appearances).In 1993, Ireland put her name on a line of socks for Kmart which became a bestseller. The retailer subsequently gave Ireland her own clothing line.

She then founded kathy ireland Worldwide, initially a brand product marketing firm in which she and her related trusts own in its entirety.In 2004, Ireland's annual take was thought to be around $10 million, which prompted Forbes to name her the "prototype for model-turned-mogul," in an article about the trend of modelpreneurs.2005, kathy ireland Worldwide products were sold at over 50,000 locations in 15 countries, generating an estimated $1.4 billion in retail sales.According to a February 27, 2012 issue of Forbes magazine, featuring Kathy Ireland on the cover, her product line (furniture, lighting, flooring, windows, jewelry, bridal gowns, etc.) now sells some $2 billion annually at retail.In a May 2012 British Vogue article, Ireland was called the world's richest model over Anne V and Gisele Bündchen.