I found this on the Internet, but it was not complete. I completed it and added more bids for more distributions. Don't remember the originator to give them credit. There are still a few open bids.

 

To prevent confusion, upper case refers to bids, lower to suit length.

 

1) Don't miss any 8-card major suit fit.

2) 4-4 fits before 5-3 or 6-2.

3) Opener is declarer in most situations.

4) Minimal info to opps.

 

3C response forces 3D. Then 3H=4s, 3S=4h, and 3N=both. Modified for opener 5-card major, responder 5-4 or 6-4, and slam bids. In case opener and responder both have 5-card majors, opener may refuse a transfer when 5-2 in majors by bidding 3N. Responder may make another transfer to play in a major.

 

Drawback 1: 3C-3N gives much info to opps. Bid needed for all possible responder major 5-4.

 

Drawback 2: Gives away opener's 4-card spade suit when responder searching for opener's 5-card major.

 

Opener must be no worse than 3-2 in majors and no better than 4-4 or 5-3.