I think that punishment, consequences, discipline...and any other terms like that are just slightly different shades of gray for the most part. (I'm not getting into abuse and that sort of thing). Personally I think that the most important thing to consider no matter what you do is whether your child feels respected.
I believe myself to be a nonpunisher (for the most part) because, to me, the term punishment relays a sort of randomness to it. For example - you didn't clean your room, so I'm going to spank you. Or you're yelling so you need to sit in a time out chair. Or since you didn't come when I called you to leave the park there is no desert tonight.
We use time outs in our family, but I don't view them as really artificial punishment. If you're two and you're having a major tantrum, screaming and thrashing around in the middle of a board game your siblings are playing, I think it's time for you to take some time out and go cool down in another room. That can be with or without me. That can be 15 seconds or a half hour - whatever is appropriate. I don't arbitrarily assign a time to it...sometimes the second we leave the room the tantrum starts. Sometimes they just want to cuddle on my bed for a while. Sometimes they seriously want to be left alone for a while. My oldest gets frustrated easily. While I would like to talk to him about the way he's behaving, sometimes it just isn't feasable at a certain point in time. Sometimes I have to ask him if he needs to 'take some time'. He'll either tell me he does, and he goes up to his room (again, sometimes with me, sometimes not) and lays in his bed or plays or whatever until he's ready to deal with the situation. Sometimes the two oldest are just AT each other and I cannot deal with it and I ask that we all have some time. They separate, I get a few minutes peace to gather my thoughts and calm down.
Geez, it sounds like we do this all the time. But really, there is usually some reason behind the behavior and we get to the bottom of it. Hungry? Thirsty? Tired? Overstimulated? Annoyed cause your little sister won't leave you alone cause she's hungry? We just can't always get there right away with emotions flying.
I also use other consequences, lest you think that is the only thing in my parenting toolbox. But again, they aren't arbitrary; they aren't me thinking up ways to make my kids miserable when they misbehave to deter them from it. If there are toys all over the living room and we're expecting company and the kids won't pick them up they know that I will. However, because I usually have alot of other things that I need to do I probably won't have time to put them where they should be. Chances are I'll just grab a bag or a box, toss them all in and stick them away in a closet to be dealt with when I have time. If bedtime is dragging on and on and on (we have tried doing away with it and it just didn't work for us for reasons I won't get into here) and dd is not getting there until a half hour after it hits, she knows that I will be asking her to get ready a half hour earlier because there's only so many nights I can deal with a desperatly tired five year old who just can't stop crying (she gets VERY emotional when she's tired. Takes after me
Anyways, I do think it is possible in an ideal world (one where moms are never sleep deprived, stressed out, or having to deal with evil reletives) to raise a child without punishment - based on what I view as punishment.