And, now for a different approach...
I'd suggest thinking about your long term goals. My goal is to raise a child who thinks critically, cares about himself and others and thinks through the consequences of his actions so he's guided to make wise decisions. I believe that end goal is best served by lots of plenty of respectful discussion and by practice learning to make decisions especially when the child is younger and the risks of a bad decision aren't as high. If all the child has learned is 123 time out they aren't really learning how to make appropriate decisions or consider the needs of others.
In my opinion simply demanding obedience for obedience's sake gets us away from achieving these goals. Children who are taught to be obedient can easily transfer that obedience to someone else who doesn't have their best interests at heart - an influential but bad influence peer, a bully, a creepy person who wants to take advantage of them, etc.
I won't always be there so I want a child who can ask questions, weigh moral decisions and think for himself. Telling a kid do as I say now and don't ask questions is not the road to getting there. I don't want the kid who jumps off the bridge because someone else tells him to, but instead would prefer the kid who isn't afraid to say jumping off the bridge is a bad idea and here's why I'm not doing it. Also, the reality is especially as kids get older our power to force them to comply is really quite limited as they can learn to sneak, break rules, etc. I want the child who does what is right even if I'm not there to make him.
That said, obviously there are certain matters of dire health and safety where compliance needs to be required and even in these situations the likelihood of getting compliance will increase if the child really understands the whys of the situation. It has also been my experience when your child understands you aren't a micromanager who doesn't trust them, on the big stuff they listen because they get the gravity of the situation if you are so serious about it.
Books I suggest:
http://www.amazon.com/Kids-Are-Worth-Giving-Discipline/dp/0380719541http://www.amazon.com/Kids-Parents-Power-Struggles-Lifetime/dp/0060930438/ref=pd_sim_b_4
