If you are looking to begin a debate with gin lovers, this is the question to ask. Traditionally, a gin and tonic are served in a tall, thin glass commonly referred to as a highball glass. In the past several years, the trend, and more widely accepted practice, is to serve a gin and tonic in a large bulbous glass called a “Copa de Balon.” This wide-mouthed glass is believed to allow more aromas to escape thus giving the drinking an all-around experience. Which is best, is entirely a personal preference.