I'm surprised you aren't asking about behaviour management rather than discipline. The term discipline can have quite negative connotations where the focus is often on punishment. (Sorry, but am a bit of a pedant.)
I used to work with schools devising behaviour policies. And now am a parent of 2, so have seen it from both angles. Many schools are more enlightened about BM than they used to be years ago, especially in inner city schools where there can be very dynamic BM demands and staff are required to act as a team to manage what goes on. My daughter's school has a golden time system which only has value for some of the pupils, so one of the key secrets to successful rewards systems is to find rewards that have value for as many pupils as possible. I don't think her school have got the hang of BM at all - there is no whole school approach, and they don't seem to know what to do with 'repeat offenders', who all just seem to get bawled out by the head and then sent home. There is so much more they could be doing.
To be honest, the best practice I've seen in schools has been where BM is a low-key, supportive approach that doesn't require huge amounts of attention because the school are aware that positive relationships and bolstering pupils' self esteem are key factors in keeping negative behaviour to a minimum. If the pupils feel that they can achieve their best, develop their strengths and support others in doing the same, it makes it a happy place to be (and for everyone, not just the children.)
The importance of a well-taught, stimulating and relevant curriculum cannot be underestimated in keeping pupils focused on their primary purpose (also good lunchtime experiences help - good play equipment, shelter, quiet places, inclusive games, nice environment, lunchtime clubs, etc). Prevention is better than cure.
Schools that regularly review behaviour policies and take a whole school approach (e.g. involving midday supervisors as well as class teachers, TAs and pupil representatives) have the best successes, IME. It will have limited success if treated in isolation, though. Regular review of teaching strategies and curriculum go hand in hand with it. If the children are bored, or have the wrong targets/strategies, it is bound to cause mischief.