Steve Wynn is well known for his expansion of Las Vegas during the 1990's. Wynn's father owned a series of bingo parlors, he died during open heart surgery shortly before Wynn graduated from college, resulting in Wynn taking over the family's bingo business in Maryland. He made enough money to buy a small stake in the Frontier Hotel and Casino in Las Vegas. The Wynns moved to Las Vegas from their Maryland home in 1967, with Steve becoming an executive and part owner of the Frontier Hotel. Between 1968 and 1972, Wynn also owned and operated a wine and liquor importing company.

During the early 70s Wynn used profits from a real estate transaction to buy a controlling interest in a downtown casino called the Golden Nugget. Wynn renovated, and expanded the Golden Nugget into a four diamond resort with great success in attracting upmarket clientele to downtown Las Vegas. He later built a Golden Nugget Hotel Casino on the Boardwalk in Atlantic City in 1980.

The Golden Nuggets sale in 1987 for $440 million allowed Steve Wynn to focus on the design and development of his company's flagship property, The Mirage, which opened in 1989. In 1993 Wynn opened Treasure Island next to The Mirage, a four diamond resort, highlighted by entertainment from Cirque du Soleil. In 1998 Stephen Wynn opened the Bellagio, one of the most spectacular hotels in the world, which included an artificial lake, indoor conservatory, an art gallery and high-end boutiques and restaurants expanding on his luxurious resorts.

Wynn's company Mirage Resorts Inc. also developed casino/hotels in other locations around the United States including of a resort in Biloxi, Mississippi opened in March 1999. In 2000 the MGM purchased Mirage Resorts Inc to form MGM Mirage, and Wynn stepped down as Chairman.

Steve Wynn then purchased the Desert Inn Hotel in Las Vegas tore it down and built his largest resort yet, the Wynn Las Vegas, which opened in 2005.