Precision 1CA combination of natural, two-suited and pre-emptive bids, on the principle that Precision is a powerful weapon once the other side have been allowed to exchange a few bids, but it's very vulnerable to aggressive overcalls. It's much more disruptive (and safer) to overcall the 1C immediately than to back in on the second round, incidentally.
Polish ClubA vaguely Precision-like system, popular in Poland.
Mini 1NT10-12 balanced is the most common range, but some are even weaker.
Multi 2DAssume that the multi bidder has one of the weak options for his bid, since those occur much more frequently than the strong ones. It is also important to bid aggressively on the first round of bidding after the multi has been opened, before opener's partner knows what type of hand he's facing.
Flannery 2DFlannery is a 2D (or occasionally 2H) opening to show very approximately weak no-trump strength, i.e. (10)11-14, 5+ hearts and exactly four spades. This is neither a weak nor a particularly strong hand, so our overcalls could either be aggressive or a decent opening hand... we'll probably discover in time what works best.
Copyright 2015 Finn Clark.