Rodney Williams gave up a six-figure salary for start-up debt, and succeeded. Here’s how.

Rodney Williams knows a lot about the fear that goes along with becoming an entrepreneur. Six years ago, Williams left his six-figure job at Procter & Gamble to co-found a business that required racking up six figures in debt.

The risk paid off.

Today, LISNR — which develops software that enables devices to communicate via ultrasound — is being used in mobile payments, ticketing, and mobile authentication. And the company has lined up some notable investors and business partners, including Visa and Live Nation Entertainment’s Ticketmaster.

Williams, the company’s chief commercial officer, says maintaining a positive attitude guided him through the early days of LISNR. With any start-up, there are going to be many sleepless nights. Williams says you need to wake up with a smile on your face and have “delusional optimism.”

Williams also said his humble upbringing, and his mother’s guidance, have helped him to remain positive in times of stress, and made him more resistant to fear.

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