This is a tough question that all parents face. Modern parenting and modern society deem smacking as a negative method of bringing up a child.
Well, the truth be told, I was brought up by a very strict and fierce mother who would not think twice about giving me and my siblings the cane to enforce proper behavior in us. My siblings and I were beaten whenever and wherever we were naughty and not behaving as my mother saw fit, which was to speak politely when you are spoken to, to not touch other people's belongings, to not accept any gifts or treats from strangers and friends without first asking her, to study hard, and to not fight with other children, even if we did not start the fight. So, my siblings and I were brought up with the strictest rules and without our voice heard at home, but did that hurt us? Frankly, I do not believe that it has. I guess in this day and time, my mother would probably be brought up for child abuse, which I would find rather silly.
And now that I am a parent myself, do I practise smacking my kids? No, not really although I have smacked my kids probably about a handful times and all for very good reasons where extremity in disciplinary action was required. The first time I spanked my daughter was when she was about three years old, and tried to poke her fingers into the electric socket many times although I held her back and said no each time she did it. So, the next time I caught her doing it, my immediate action was to smack her really hard on her hand, and told her firmly "no"! That final action that I took shocked her, and luckily it prevented her from ever trying to do that again. My son, too has had a few caning from me, mostly for his school work and bad behavior. Normally, I would like to sit my children down to speak to them about their wrongdoings. I would give them about three chances and warnings for the same mistake or action if I catch them doing it again, before I force myself to bring the cane to smack them. This I have practised from the time my children were old enough to understand the meaning of smacking and pain, and they are both well-balanced, healthy young teenagers now. And I am glad to say, smacking punishment is a thing of the past for us, but it was very useful when they were younger.
Therefore, based on my experience with smacking, I feel that smacking, as one form of disciplinary action is good, provided it is used properly. Smacking does not mean abusive beatings. That would be totally wrong. It can only work if it is used sparingly with the right tool, in the right bodily spot, such as the hand or bottom and with young children. If your toddler were about to do something dangerous, life threatening such as playing with fire, electricity, running out to the street inspite of you trying to hold his/her hands and keep him/her by your side, then a light smack on the hand or bottom would seem appropriate to bring attention to his/her wrongdoings. On top of that, it would be wise to sit him/her down and speak to him/her until he/she understands his/her boundaries of what he/she is allowed to do and what is not appropriate. For older aged children (from the age of ten and above), I find smacking less effective, and should not be used at all. What I believe we can do as parents, is to set good practices, boundaries and rules for our children from the day they were born, and be consistent in their upbringing in the house, so that it becomes the normal practice for them as they are growing up.
As parents, we must not stress ourselves out on what is the right or wrong ways of parenting. But we can make it easier on ourselves by learning from our parents's ways, and adapting it to suit our style of parenting. Most importantly, consistency and routine is important from day one and as they grow into teenagers and young adults, communication between parent and child should be kept open at all times.