Transfer Advances Overview
A transfer advances is a competive bridge convention. It is also referred to as a Rubens Advance.
When you partner makes a suit overcall and your RHO passes, you are faced with the problem of how to show weak, invitational and game-going hands. A simple raise is insufficient, double raises are generally considered weak/preemptive in nature. Bidding a new suit is unclear (by partnership argreement) on it's value. The biggest benefit of the Transfer Advance is the useful space principle. It makes it easier for the advancing partnership to describe their shape and strength.
This convention uses transfer as a chain of bids to retain the captainency in the auction in order to bid stronger hands. Advancers bid is a transfer (one below the suit they's like bid) and requests the overcaller to bid it. Assuming the opponents continue to be silent. The advancer is in a position after the transfer to pass (weak with this suit preferred as trump), rebid overcaller's suit (weak with support and the transfer suit indicates a lead choice if the opponent's get into the auction).
A transfer into partner's suit shows an invitational raise. Typically 9-11 HCP (and some shortness points) or better. Raising the advancer is not a transfer to the next higher suit, but a simple raise (6-8 HCP), 3-card support.
The important element to remember is that bidding the open's suit is not a 'cue-bid' to show a limit raise hand; it's a transfer. The limit raise is a bid one under the overcaller's suit.
Another stumbling element in the convention is reaching a partnership agreement on the meaning of the advancer bidding 1NT (natural; stopping in open's suit) rather than a transfer to 2♣. Also, what does a transfer into the opener's suit mean?