Meckwell

2NT in response to 1 of a minor opening is Game Forcing and may contain one or both 4 card Majors.

If opener has 1 or both 4 card majors they bid 3 (Checkback Stayman), even if he has an honest club suit.

The beauty of the convention is that you know you are going to game, just a question of where.

Rumor has it that this was devised by Eric Rodwell and Jeff Meckstroth when they played Pro and didn't want their clients to be playing the NT contracts.