In swedish bridge most people using a variant to Jacoby 2NT called Stenberg 2NT.

 

Either 2NT is gameforcing or invinting after a 1Major opening

 

1H - 2NT

3C -           Minium

3D -           15/16+ GF and no singeltons

3H -           Extra values and Club singelton

3S -           Extra values and Diamond singelton

3NT -        Extra values and singelton other Major

4 C/S/H     void

 

After showing minimum 2NT bidder can GF with 3D and ask for singeltons.

1H - 2NT

3C - 3D   

Same as above except 4th level.

If no singeltons 1H opener always bid Cuebids on 4th level.

 

I like the convention and makes it more easy to either stop in time or find the nice fit slams.

 

/Stefan