Smolen
The basic idea of Smolen is to get strong 1 NT opener to declare. Responder has 5-4 or 4-5 in the majors or better.
- 1NT-2
-2
-3
forcing with 5 or more 
and 4 - 1NT-2-2-3 forcing with 5 or more and 4
With 6-4/7-4 when opener has bid 3NT after Smolen you then transfer into your 6 or 7 card suit
1NT-2-2-3/3-3NT 4 is transfer to Hearts 4 is transfer to Spades