- After weak 1NT, if responder use Stayman or transfer, Double not lead directions,

  just shows strength

After Double

                      2X                 

X                                 ?

                      1NT

                                            - X                  : negative

                      2X                   

X                                 Pass                        

?                  

                      1NT

                      Pass

- X                  : negative

                      2X                   

X                                 Pass                        

?                  

                      1NT

                      2Y

- X                  : negative

                      2X

                      Pass               

X                                 Pass                        

Pass                   ?

                      1NT

                      2Y

                                            - X                  : negative

           Pass    

X                                 Pass                        

?                  

           1NT

           2X

- X                  : penalty

- Pass            : forcing

           Pass

           Pass    

X                                 Pass                        

Pass                   ?

           1NT

           2X

                                            - X                  : penalty

Rules:

- After Pass use Dobi Double

- After penalty Pass or penalty Double, new Double also penalty