Webb came to Las Vegas as the general contractor in 1946 for the construction of the Flamingo Hotel, and completed construction projects at such Las Vegas landmarks as the Sahara, Caesars Palace and the Las Vegas Hilton.

Webb is best known for his achievements as a builder and real estate developer. In 1960, he built Sun City near Phoenix, Arizona, one of the first master-planned, age-restricted communities in the United States.

Starting with the Sahara in the 1950s, Del Webb and his publicly-traded companies bought into the casino business as owners. Eventually, the Webb portfolio included casinos in Nevada and New Jersey. The most famous Webb properties were the Sahara on the Las Vegas Strip, the Mint in Downtown Las Vegas, and Atlantic City's Claridge casino.

In 1962, when Del Webb assumed sole ownership of the Sahara and Mint, it became the first publicly-traded company to own a casino outright.

Although Del Webb's company divested itself from the gaming in the 1980s, its legacy as both a builder and an owner remains strong.