| 
    
    Keycard 
    Blackwood - A slam bidding variation from regular Blackwood, designed to 
    increase the accuracy when considering the potential to reach slam or 
    grandslam.  This method recognizes the trump King as equivalent to 
    other Aces, thus five "aces" or keys are considered. In response to a bid of 
    4 Notrump (Blackwood): 
      
        | Response | Meaning |  
        | 5C | 0 or 4 keys |  
        | 5D | 1 or 5 keys |  
        | 5H | 2 keys |  
        | 5S | 3 keys |  
    Note: The 
    Keycard Blackwood methodology has given way to the 
    Roman Key Card Blackwood 
    (0314) and Fourteen Thirty (1430) conventions. Also 
    see books on
     
        Slam and other slam conventions:
     
        1430,
        Baby Blackwood, 
        
        Blackwood, Controls,
    Exclusion Blackwood/Voidwood,
    Gerber,  
        Grand Slam Force,
    Jacoby 2 Notrump,
    Key Card Blackwood, 
    Kickback,  
        Last Train,  NAMYATS,
    Pick a Slam,
    Quantitative Notrump Bid,
    Rolling Blackwood,
    Serious 3 Notrump,
    Slam Try - Stayman,
    Splinters,
    Opener 
    Jump Shift,
Strong Jump Shift, and legacy treatments as 
        Roman Asking Bids,
    Roman Blackwood, 
        Roman Gerber.  Slam 
        treatments 
    also include interference of 
    an overcall by opponents, as 
        Negative Slam Double,
    DOPI,
        DEPO, ROPI. |