They say you should love what you do – and for some couples, their business affairs are intimately tied to affairs of the heart. From the founders of the Gap to the people that brought us Little Caesars Pizza, read on to discover the couples that went into business and made billions in the process. All dollar amounts in US dollars.

Married couple Pan Shiyi and Zhang Xin founded real estate developer Hongshi, now Soho China, in 1995. When they met, Pan was already working as a real estate investor, while Zhang was a factory worker. She went on to study a master's degree at Cambridge University and became an investment banker. Together, the couple are worth $3.1 billion (£2.27bn), with Pan serving as the company's chairman and Zhang as the CEO. According to Zhang, she and her husband are truly self-made billionaires. "We are not the sons and daughters of anybody. Nor do we have powerful friends. We don't socialise much."

Soho China, which develops office towers in Shanghai and Beijing, is listed on the Hong Kong Stock Exchange (HKEX). In June 2021, US private equity firm Blackstone said that it would buy the majority of Soho China for $3.05 billion (£2.2bn). It later pulled out of the deal due to regulatory complications, as Zhang and Pan were accused of trying to "cash in" on their business and "flee" to the US, according to reports in the Financial Times. Soho China is now being investigated by the Chinese authorities over alleged tax evasion.

Donald and Doris Fisher opened their first Gap store in 1969, after Donald struggled to find jeans that were the right length. Selling Levi's jeans and music records to a target market of 12-to-25-year-olds, the store was originally going to be called 'Pants and Discs' until Doris suggested 'the Gap', inspired by the 'generation gap'. The company went public in 1973 and now owns clothing brands Banana Republic, Old Navy, and Athleta.

Between 2015 and 2020, the Gap's stocks fell by 40% and the Fisher family saw a $2 billion (£1.4bn) decline in their fortune. However, they still have a net worth of $8.9 billion (£6.5bn), despite the brand's struggles. Don died aged 81 in 2009, but the now-global firm is still very much a family affair. Doris has been named the honorary lifetime director and the couple's three sons sit on the company board. 

Tom and Judy Love have been married for 60 years. Over that time, they've amassed a net worth of $9.1 billion (£6.67bn) through their chain Love's Travel Stops & Country Stores. In 1964, the couple borrowed $5,000 from Judy's father to lease a gas station in Oklahoma. Today, the small pit stop has grown into a national chain with annual revenues of $20.6 billion (£15.1bn). It remains family-owned, with three of the couple's four children working for Love's. 

According to Tom, Judy worked as the company secretary when they first launched their business – and had to manage all the books as Tom couldn't even balance his own chequebook. "When we began, it was just she and I," he said. "And I don't say this gratuitously. I really don't, but it wouldn't have happened without her. She really played a central role for a long time, and still does today."  

In 2005, computer scientist Paul Graham and investment banker Jessica Livingston launched the start-up incubator Y Combinator with co-founders Robert Morris and Trevor Blackwell. It's now the world's largest accelerator, with a $300 billion (£220bn) portfolio that includes Dropbox, Airbnb, Stripe, and Reddit. 

Graham had worked with Morris and Blackwell before. The trio launched Viaweb in 1995, a web application that later became Yahoo! Store. But he says that it was Livingston, his then-girlfriend, who "literally made YC" and nurtured its "nexus of people." The couple married in 2008 and, although they no longer work at Y Combinator, they have an estimated net worth of around $53 million (£38.8m), according to various sources. 

In 1993, Kate Brosnahan – who worked in the accessories department at Mademoiselle magazine at the time – launched her eponymous designer brand Kate Spade New York with her future husband Andy Spade, an advertising executive she'd met at college. By 2006, the couple had sold their shares in the company and walked away with a reported $93 million (£71.3m). “We knew it would have to be creative,” Andy Spade said of their venture. “We weren’t businesspeople. The idea – it wasn’t to be big. It was just to try something.”

In 2017, design house Coach bought the Kate Spade brand for $2.4 billion (£1.8bn). However, having sold their shares already, the couple didn't receive a penny from the acquisition. The year before, they'd launched a new in-house accessory line called Frances Valentine after their daughter and a favourite family name. Sadly, the rest of the story isn't a happy one. Kate and Andy separated in early 2018 and she tragically took her own life that June after struggling with depression and anxiety for many years. 

Do Won and Jin Sook Chang came to the US from South Korea in 1981. Three years later, they used $11,000 in savings to open a clothing store in Los Angeles. What began as Fashion 21 soon became the global fast fashion brand Forever 21, and at the height of its success the couple had a combined net worth of $5.9 billion (£4.3bn). However, the business later fell on hard times...

In 2019, the company filed for Chapter 11 bankruptcy and announced that it was ceasing operations in more than 40 countries. The following year, Forever 21 agreed to sell off its assets to a consortium of mall operators for $81 million (£59.7m). Although their fortune took a tumble, Don Won and Jin Sook Chang still have an estimated net worth of $1.5 billion (£1.1bn).

Newlyweds Gordon and Carole Segal were just 23 when they scraped together $17,000 from savings, wedding money, and a loan from Gordon's father. They used the funds to open their first store in an old elevator factory in Chicago in 1962. Named Crate & Barrel after the crates and barrels they upturned to use as fittings in-store, the business is now an international brand that sells home decor in North America and Europe. 

Today, the brand is owned by German e-commerce company Otto Group and has yearly revenues of $1.6 billion (£1.2bn). Carole went on to found the gourmet food store Foodstuffs, while Gordon worked as the CEO of Crate & Barrel until 2008. He's described each Crate & Barrel store as a stage, with employees working as actors and customers forming the audience: "and it is the job of the actors to convince the audience that this is a good play – a good product." The couple has three children and online estimates suggest that their net worth is around $500 million (£368.3m). 

British couple Sir Philip and Lady Cristina Green are best known for having owned a selection of fast fashion brands – including Topshop, Topman, Dorothy Perkins, and Miss Selfridge – through the Arcadia Group from 2002 to 2020. Cristina, or 'Tina', is the majority owner of Arcadia's parent company Taveta Investments. The Greens married in 1990 and their business journey began when they bought the department store British Home Stores (BHS) in 2000. They followed this purchase with the acquisition of the Arcadia Group in 2002. They have two children together, as well as two from Cristina's first marriage. 

Sir Philip (pictured with Cristina and their daughter Chloe) has been at the centre of controversy for years due to a pension scandal at BHS, which he sold for just £1 ($1.364) in 2015, as well as allegations about his behaviour towards staff. "I've given everybody at Arcadia an entrepreneurial spirit," he once said. “We don't have a lot of ranting and raving, we just get things done.” In 2020, however, Arcadia went into administration and Topshop, Topman, and Miss Selfridge were snapped up by online retailer ASOS. The couple still has a combined net worth of $2.4 billion (£1.7bn). 

Kevin and Julia Hartz met at a wedding in 2003. He had already founded two start-ups, including the billion-dollar money transfer site Xoom, while she worked for MTV. Before they even moved in together, the couple apparently knew that they wanted to start a company – and in 2006, they launched ticketing platform Eventbrite with co-founder Renaud Visage. 

In 2016, Julia took over the role of CEO from Kevin, who stepped down due to an undisclosed but non-life threatening illness in 2015. Eventbrite went public in 2018 with a share price that valued the company at $1.8 billion (£1.3bn). Julia has said: "I never considered myself an entrepreneur until I met Kevin and he made it look so easy. He helped me tap into a passion I didn't even know I had." The couple has two children together and an estimated net worth of around $18 million (£13.3m). 

Gianluigi Aponte was a ship’s captain who met Swiss tourist Rafaela (pictured together with actor Gerard Depardieu, left) when she was a passenger on his boat. In 1970, they launched a cargo shipping venture, Mediterranean Shipping (now MSC), with $5,000 in savings. MSC is now the second-largest shipping line in the world after AP Møller Maersk. 

Captain Aponte is still the group’s executive chairman, although he retired from day-to-day activities in 2014. Former Maersk COO Soren Toft is now the company's CEO. According to Forbes, Gianluigi and Rafaela Aponte have a net worth of $11.1 billion (£8.2bn). The company’s tagline is: “Land covers one-third of the Earth – we cover the rest.”

With a net worth of $8 billion (£5.9bn), Stewart and Lynda Resnick own the Wonderful Company, which has Fiji Water, POM Wonderful pomegranate juice, Wonderful pistachios and almonds, and Halo mandarins under its wings. Both divorcees with children, they met in 1970 when Stewart was searching for a marketer for his janitor business. They married in 1979 and began their business career by buying the failing flower delivery service Teleflora. 

The Resnicks bought land in California in 1978, which kickstarted their foray into agriculture. They now own a majority stake in one of California’s largest underground water storage plants. Nearly half of all Americans regularly purchase one of their products and The Wonderful Company has annual revenues of over $5 billion (£3.6bn). "It takes a nut to sell a nut," Lynda has said. 

Former baseball player Mike and wife Marian Ilitch met on a blind date and got married in 1954. They used $10,000 in savings to open their first Little Caesars Pizza in 1959, taking the name of the restaurant from Marian's nickname for Mike. 

Mike Ilitch sadly died in 2017. Marian, who's now 88 years old, has a net worth of $4.4 billion (£3.2bn) and also owns the Detroit Red Wings ice hockey team and MotorCity Casino Hotel. Meanwhile, the Detroit Tigers baseball team, which Mike bought in 1992, is held in a family trust.  "Early on, Marian and I decided that we wanted every one of our businesses to remain family owned,” Mike Ilitch said when his daughter Denise and son Christopher became co-presidents of Ilitch Holdings in 2000. 

Jo Malone married Gary Willcox (pictured with their son Josh) in 1985 and he gave up his career as a surveyor to join her in her eponymous London-based candle and scent business. They sold it to Estée Lauder for "undisclosed millions” in 1999.

Malone stayed on as creative director but left in 2006 after undergoing treatment for cancer. Under the terms of her contract she couldn't start a rival business for five years, but in 2011 the couple started a new fragrance company called Jo Loves. Of her husband and business partner, Malone says: “He’s the business brain. There would be no Jo Malone or Jo Loves without him.”

Bill Gates was the CEO of technology giant Microsoft, which he co-founded in 1975, when he asked the company product manager Melinda French out on a date in 1987. They married in 1994 and have since put more than $35.8 billion (£26.5bn) into the Bill & Melinda Gates Foundation, the world's largest philanthropic organisation. 

Through their foundation, the couple (pictured in 2002) has worked to improve global health and reduce child mortality, aiming to eradicate diseases such as polio and malaria through vaccination programmes. They've also worked to control the spread of tuberculosis and HIV. After 27 years of marriage, however, Bill and Melinda announced that they were divorcing in 2021 but would continue to work together on the foundation, which they co-chair. Melinda, who has a net worth of $6.3 billion (£4.6bn), said: "We continue to share a belief in that mission and will continue our work together at the foundation, but we no longer believe we can grow together as a couple in the next phase of our lives." Bill is currently the world's fourth wealthiest person, with a fortune of $138.5 billion (£103.3bn). 

Diane and Ken Hendricks met when she was selling customer homes on behalf of a builder and he was a roofing contractor working for his father's firm. In 1982, they pooled their knowledge of the housing and home improvement markets to found ABC Supply, now the largest roofing and vinyl siding wholesale company in the US. Ken died after a tragic accident in 2007 and Diane has run the company ever since. She negotiated two of its biggest acquisitions, buying rival firm Bradco in 2010 and distributor L&W Supply in 2016. ABC Supply reported revenues of over $12 billion (£8.8bn) in 2020, according to Forbes. 

In 2018, Forbes ranked Diane as America's richest self-made woman. Her net worth is currently $11.9 billion (£8.8bn) and five of the couple’s seven children have vice-presidencies in the business. "I'm the one out front, getting things started," Ken once said of their working relationship. "Diane is the finisher, taking things down to the last detail."

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