Good bidding is based on the understanding of principles rather than on learning what bids mean. A good system has structure that helps you memorise and guides you when you are on unfamiliar ground.
UNDERSTANDING THE UNCONTESTED AUCTION is based on Acol with 4-card majors and a weak no-trump. It aims to help aspiring players in a sympathetic and logical manner to bridge the bidding gap between themselves and the experts. You can use it either as a complete modern bidding system or selectively to improve your general standard of bidding.