This is the classic Italian party drink, perfect for summer drinking.
1 ounce London Dry gin (or similar style)
1 ounce sweet or bittersweet vermouth
1 ounce Campari
lemon or orange twist (or both)
Combine ingredients in a stirring glass and fill with ice. Stir thoroughly and strain into short or copa glass. Fill with crushed ice. It can also be served neat, in a small wine glass. Garnish with citrus twist.