Stelios, who is best known as a serial entrepreneur, is the son of the late Loucas Haji-Ioannou, the Greek shipping magnate. Loucas provided the seed capital for Stelios’ independent business career, which started when he created shipping company, Stelmar, at the age of 25; Stelios went on to float the company on the New York Stock Exchange in 2001. In 1995, three years after founding Stelmar, Stelios established easyJet, the low-cost airline, which floated on the London Stock Exchange in 2000. Although Stelios stepped down from the easyJet board in 2010, he and his family remain the airline’s largest shareholders.

True to his beliefs in serial entrepreneurship Stelios consolidated the ownership of the easy brand into his private company, easyGroup, and launched several easy-branded businesses dedicated to delivering great value, low-cost services to consumers. The group acts as an umbrella to a number of companies including easyBus (airport transfers), easyOffice (low-cost, serviced office rental for small businesses), easyHotel and easyGym - easyGroup also continues to license the easy brand to easyJet plc.

In 2006, at the age of 39, Stelios received a knighthood from Queen Elizabeth II for services to entrepreneurship. Since then, he has continued his dedication to making a difference to society by launching a number of philanthropic initiatives supporting entrepreneurship, higher education and environmental sustainability.

Over 10 years, Stelios has pledged 200 scholarships to the London School of Economics and Cass Business School in London - his alma maters - supporting young, exceptional ‘Stelios Scholars’ who want to make a difference in their chosen fields. In addition to this, Stelios created the "Stelios Award for Disabled Entrepreneurs in the UK" in partnership with Leonard Cheshire Disability. The Award has been presented annually since 2007 to exceptional entrepreneurs who have overcome significant physical and perceptual limitations in starting their businesses (www.lcdisability.org/stelios).

In Cyprus, the birthplace of his parents, the Stelios Award for Business Cooperation in Cyprus was established in 2009 to recognize entrepreneurs who are committed to bi-communal trade between Greek and Turkish Cypriots on the divided island.  Stelios also strives to further inspire entrepreneurship in Greece, his own birthplace through the "Stelios Award for Young Entrepreneur of the Year", a 50,000EU prize given to an outstanding entrepreneur under 40 years old.

Stelios began his environmental work in 1992 when he co-founded CYMEPA (www.cymepa.org), an association dedicated to preserving the marine environment in Cyprus, the birthplace of his parents.  More recently, Stelios supported environmental research and education on the island by helping to fund the Stelios Environmental Centre in Pedoulas, his father’s village.  In Greece, his own birthplace, Stelios has continued his commitment to environmental protection by supporting the Pendeli Reforestation project.

2010 marked the first year that Stelios, through the Stelios Philanthropic Foundation, sponsored Clean Equity Monaco: an annual conference bringing together diverse players in the dynamic clean-tech sector. Here, Stelios presented the "Stelios Award for Young Clean-Tech Entrepreneur of the Year” celebrating innovation and entrepreneurship in Monaco. In 2009, Stelios was also nominated the Honorary General Consul for the Republic of Cyprus in the Principality of Monaco. 

His interest in and commitment to WWF and its work has also spanned a number of years.  His support and participation has included membership in the WWF International 1001 Club, and involvement in the establishment of WWF Greece. Stelios joined the WWF-UK Council of Ambassadors in 2009.