I have had the same problem with my son but he has been suffering from a cold and ear infection for nearly 4 weeks now ... I started to bring him in bed with me as it was the only way he would settle and, like you, we both work 5 days a week.
This past week I have decided enough is enough and I have literally camped out at the side of his bed if he wakes and cries - this is normally 2-3 times at the moment. I go into his room when he really starts crying to find him standing up. I find his dummy and lay him down. I then lay at the side of his cot, on the floor, with my arm touching his belly, back, hand, etc through the bars. He does toss and turn sometimes but normally within 20 mins (max) he is asleep --- I then return back to bed. Before all this happened he slept right through so as you can imagine its getting is all out of routine.
Hope this helps .... persist and remember - WHEN YOU LAYING AT THE SIDE OF HIS COT ONE NIGHT, I PROBABLY AM TOO ... TEXT ME!! LOL!! xx