Lots of books available on this - it's a multi-light set-up, possibly with a snoot on the main light, placed upper-right.
Another fill light on the left at about 1/2 output (from the main) and a background light at about 1/4 output to lift the background...
Working-out lighting set-ups is dead aeasy once you know what to look for - shadows and catchlights.
We used to have to work out lighting from one another's photos when I did my advanced courses...you can usually place the lights to within a 1/4 metre of what was actually used with a bit of practice...
Oh and this one is tungsten-light, not flash, which accounts for the 'soft' look...