Philip Duff owns the on-trade consultancy Liquid Solutions. He founded Holland’s first speakeasy bar—Door 74 in Amsterdam—and owns the award-winning Old Duff Genever brand. Duff has published articles in Drinks International, CLASS magazine, Imbibe UK, Mixology (Germany), Australian Bartender, and Reuters. He also serves as the educational director for Tales of the Cocktail and is a judge for the IWSR, the World’s 50 Best Bars, and the Spirited Awards. He lives in New York City with his wife, stepdaughter, and a crested gecko.