In 2007, Kristo and his friend Taavet were two Estonian friends living and working in London. They quickly realized how expensive it was to exchange money between Pounds and Estonian Euros. Their hack to this problem ended up becoming the foundation for their startup, Wise, which they founded in 2011. Today, Wise allows people to hold 56 currencies, move money between countries, and spend money abroad. Not only is Wise one of the world's fastest-growing tech companies, it was recently listed on the London Stock Exchange in a direct listing that valued the company at $11 billion. Kristo shares why demand for Wise is still growing at a rapid clip, why he's personally eager to get back to the office, and why saying thank you is critical.