Fever Tree is a producer of cocktail mixers based in London. Founded in 2000 by Charles Rolls and Tim Warrillow, Fever Tree avoids the use of artificial chemicals, high fructose corn syrup and preservatives. The company is named after the cinchona tree (or fever tree), the source of quinine.
The Fever Tree line includes soda and tonic water, ginger ale and ginger beer, lemonade and bitter lemon (a blend of lemonade and tonic). While their products are more expensive, the use of naturally sourced ingredients gives their mixers subtlety and more complex flavors than their competition.