Isadore Sharp knew nothing about the hospitality industry when he started building hotels in 1961. But he had an instinct for what customers wanted and the willingness to go to great lengths to get it for them. To achieve the quietest rooms, for example, he made sure no plumbing touched concrete. To encourage personalized service, he gave everyone from parking attendants on up the authority to act instantly when a guest makes a request. That commitment to service has become the hallmark of the Four Seasons chain. Sharp, 84, remains chairman of the company, which manages 96 hotels and resorts (they collectively generate $4 billion in annual revenue) in 41 countries. To this day, he says, if developers want to launch a new Four Seasons, “we control what will be built and hire the people who will work there. We don’t franchise the name.” Sharp’s story:

I never thought about going into business. My parents were immigrants who had moved from Poland to Israel in the 1920s, then to Canada, where I was born in 1931. Downtown Toronto back then was a Jewish ghetto, and my father built houses. My mother would take in boarders, and if someone liked the house, she’d sell it. So we moved 15 times by the time I was 16.

During the summers, I’d work construction with my father and enjoyed it. I went to Ryerson Institute in Toronto and studied architecture because I thought construction was going to be my career. After graduating, I went to work with my father.

Many parts of our lives are circumscribed by chance events and coincidences. In 1955 a friend decided to build a small motel and hired me to do it. I thought, If a motel on a limited-access highway was successful, why wouldn’t it work downtown? So I decided to build a motel in the inner part of the city. It took me five years to convince anyone to invest in it.

Fortunately, my brother-in-law, his friend, and my dad each put up $90,000. I borrowed $125,000 from the Bank of Nova Scotia and got the rest from Cecil Forsyth, head of Great-West Life Insurance. We leased furnishings and got the sub-trades to wait for part of their money until the hotel opened. The hotel cost a couple million dollars to build—so talk about leveraging a deal.

We charged $10 to $12 a night, a far cry from what we charge today. I didn’t know anything about the hotel business, so I hired a general manager. To me, it was just a real estate deal, a motel that I’d open and probably sell. But I knew what I wanted it to be, in terms of the nature and style of the place. I thought we should welcome customers and treat them like guests coming to our home. The motel became a great little success, so I decided to try a second. This time, it would be a 200-room resort on the outskirts of Toronto.

By then my earnings barely covered my rising family costs, but the Bank of Nova Scotia lent me $600,000; Great-West Life, the mortgage company, and my tradesmen all went along. We named it the Inn on the Park, and it became a success as well.

To celebrate, my wife, Rosalie, and I took a vacation in Europe. It was 1963, and we were on a strict, limited budget, so we decided to average costs. One night we’d stay in a city’s worst hotel, and on the second night we’d stay in the best hotel. In London we stayed at the Dorchester, and I was blown away by it. When we returned to Toronto, I happened to talk to a builder who worked for the Robert McAlpine Company, which owned the Dorchester.

That connection led to a deal to build a London hotel that we would run. The Inn on the Park London opened in 1970 and was voted the best hotel in Europe after its first year of operation. I knew it was because we’d established a new level of service that differentiated us from the competition.

Things didn’t always go as planned. In 1974 we committed to building a $25 million hotel in Vancouver that we would lease after it opened. Unfortunately, unexpected inflation kicked in, and we couldn’t make the numbers work. The owners of the land were three corporations. I told them I couldn’t pay for the cost to finish the project or the rent I’d owe them.

The owners rewrote our agreement so we could all survive, and I borrowed more money to complete the hotel. That near-ruinous experience taught me that the financial risk of building and owning hotels was too great. That’s when I decided to move from construction to the hotel business. So now we are a management company with a small interest in owning the hotels.

Throughout everything, I had a wife who never complained, and she picked up the load of being there for our four children. In 1978 our teenage son Chris died of melanoma. The loss of a child to sickness changes you forever. After Chris’s death, Terry Fox’s run across Canada to raise money for cancer, despite a leg being amputated due to cancer, truly inspired us. One of the more meaningful legacies of my life was establishing the Terry Fox Run, which raises money for cancer research.

In 1986 I decided to take the company public. I saw it as an opportunity to create liquidity in the ownership group, and another way to create exposure and brand value. Things went well until 1990, when Iraq invaded Kuwait and the West plunged into a deep recession. Our American business fell off, dropping our net profit from $17 million in 1990 to $2.8 million the next year. When the economy recovered, we continued to expand.

I had never sold any of my ownership shares, but in 1994 I decided to liquidate some of them for financial planning, so I sold 25% of the company to His Royal Highness Prince Alwaleed Bin Talal Bin Abdul Aziz al Saud of Saudi Arabia, who offered a 25% premium over the stock price at the time.

Some years later the prince spoke to his friend Bill Gates, and the three of us took the company private in 2007, in a deal valued at $3.4 billion. I wanted to create stability and certainty for the future by having ownership that would never have to sell again. I know that the legacy of the company is in solid hands, and I now own 5% of the company.

The world is now full of terror, and at no other time in our lives have we had such uncertainty. Business is able to bring people together across barriers because commerce benefits everyone. So business practices can have a profound influence on the world. Real success is dependent on how many people’s lives have been improved because of a company, and I’m proud of the many lives that Four Seasons has touched.

A version of this article appears in the April 1, 2016 issue of Fortune with the headline “Building Great Service at the Four Seasons.”