In Competition

1♣ - (dbl) - 

pass    =    weak, no 5 card M

rdbl    =    4+ card ♦, 6+ points, can hold less with longer suit

1♦/♥    =    system on

1♠    =    5+ card ♣

1NT    =    8-11, natural

3M    =    preemprive 7(6)+ cards

other    =    system on

If RE passes and doubler's partner bids, then OP with 11-13 balanced has to pass. If  doubler's partner passes, and OP redoubles, it is for SOS.

When unbalanced and 15+,  OP rebids, when balanced 17-19, she doubles for T/O.

Further developement after they double RE's bids:

1♣ - (pass) - 1♦/ ♥ - (dbl) -    ➲

1♣ - (pass) - 1♠ - (dbl) -    ➲

1♣ - (pass) - 2♣ - (dbl) -    ➲