These opening bids are / were employed in the northern parts of England for many years and are / were considered standard opening bids. Their present popularity or use has diminished and is limited to only a few remaining bridge clubs playing rubber bridge. One of the bridge clubs playing rubber bridge based on the Acol system is the Kirklanda Bridge Club of Menston, which is a village in Lower Wharfedale, Yorkshire, England. The Wharfe Valley Bridge Club offers players the experience of playing duplicate bridge.

Note: The Acol Bidding System employs opening bids with a 4-card Major suit. The Acol bridge player will notice that the No Trump range is strong as opposed to the generally accepted Acol range of 12-14, or the original Acol range of 13-15 high card points. Source.

Opening Bids Only

Bid		Strength		Meaning
1 :		12-21 high card points		Promises a 3-card plus Club suit.
1 :		12-21 high card points		Promises a 4-card plus Diamond suit.
1 :		12-21 high card points		Promises a 4-card plus Heart suit.
1 :		12-21 high card points		Promises a 4-card plus Spade suit.
1 NT:		15-17 high card points		Shows balanced shape.
2 :		22+ high card points		Shows any shape.
2 :		18+ high card points		Promises a 5-card plus Diamond suit.
2 :		18+ high card points		Promises a 5-card plus Heart suit.
2 :		18+ high card points		Promises a 5-card plus Spade suit.
2NT:		20-22 high card points		Shows balanced shape.