Mr W wants his way and will wail when it does not occur. I just ignore him when he is unfair and we are slowly weaning him of this behavior. He has been particularly bad when DW or I leave or the babysitter leaves.

Our big blowup was when he was 12 mos old and we were on the road going to the bookstore. He just lost and was screeching and wailing, so I pulled over and explained to him how unfair he was being and how we were going to the bookstore...etc. He has been a lot better since.

If he is being arbitrary, then we ignore him. If he explains what he wants then he gets it.