Las Vegas-based online retailer Zappos has announced that Tony Hsieh has retired as CEO after 20 years.

Hsieh was at first an investor in the company and became CEO in 2001.

In 2009, the company was sold to Amazon with Hsieh remaining at the helm.

In 2012, he invested $350 million into revitalizing downtown Las Vegas. The company’s announcement of his retirement also said that Zappos’ COO has assumed the role of CEO.