Cappelletti is a convention usually attributed to Mike Cappelletti and his longtime partner Edwin Lewis, but origin of the concept is also claimed by Fred Hamilton, John Pottage and Gerald Helms. Alternative names include "Capp", "Hamilton" and "Pottage". It is designed to allow any one- or major two-suited overcall of a 1NT opening. It is one of many conventions for interfering over opponents' 1NT opening. This convention is alertable.