My Laurin & klement veers to the right when accelerating sharply and veers to the left when decelerating sharply. Is this a fault with the steering geometry or the wheel alignment ?( which I understand on this car is done on all four wheels ) . The front tyres are new and all tyres are at the correct pressure.

There could be an issue with the toe angle pre-loading the tyres sidewall, another common reason is a worn engine mount off-setting the drive train.

What happened between the time everything was ok and the complaint?

Only recently bought the car so I've no history. The car is 2 years old, would the engine mount wear so quickly ? -although I admit it sounds plausable.

I cant imagine it being torque steer,so my guess is get your steering geometry sorted.

does it only do it if you are accelerating... if your alignment is out i'd have thought it would do this all the time.

tyre pressure???

A faulty/damaged tyre can cause this. Swap the tyres across, or better still use the spare (if full size) to eliminate the tyres.

Swapping tyres side to side depends on having non-directional tyres.

Actually, off the wall suggestion: If you've got directional (Arrow on sidewall points forwards when at top of wheel) or asymmetric (labelled "this side out") tyres, are they actually fitted the right way round?