Why would a doctor go and work in Africa for no wages when he or she could be earning a six figure sum back home and living a very comfortable life? And why do so many successful entrepreneurs donate so much of their income to charitable causes?

To be honest, in the past I have struggled to make sense of this.

But just recently I have started to understand exactly why these people do it, and what you can do about it.

Put simply, I believe there are two reasons why people do it. Firstly, people give their time and money to charity because it is something that they passionately believe in.

Not everyone does. Some people simply aren't bothered. Others see an orphan on TV and wants to know how to help them. They are driven by ideals.

The second reason is simply that giving feels so great - just as good if not better than receiving.

You know that feeling on Christmas morning when you hand a loved one of yours a present you know they will love and you watch their face light up as they open it?

Imagine being to get that warm, fuzzy feeling of doing something "good", something "worthwhile" with your life. That's a pretty big motivator. People who give considerable amounts of time and/or money to charity really do leave their mark on the world - they leave it a better place.

And who could possibly not want that?

So the question changes from why you should give your time or money to a good cause, to why not? Who genuinely in the western world can't give even an hour of their time or a few dollars for a good cause? And once you've done it once and felt the buzz, the chances are you'll want to do it time and again.

If you are now keen to start doing some charity work, where should you start? I suppose the easiest answers are to look around your local neighborhood for local charities you can help out with, and research other national charities on the Internet.

I decided a few years ago that I wanted to give some money each month to an environmental charity. That much I knew. But there were so many choices. And I wanted to put my money where I really thought it would have the greatest benefit - and where I would feel good about where it went.

So I actually took the time to research as many environmental charities as possible. I searched on Google and actually spent quite a bit of time on the website of each charity I found. I looked at what they stood for and what they have achieved recently. And slowly I managed ot put together a short list of charities that I felt good about giving money too.

You see, I think that too many people give to charity simply because it's "cool" - or because they'd feel unhumane if they didn't. Every time there's someone shaking a bucket or offering a sticker - there they are with their coin.

But I wanted my charity giving to mean something. I wanted to really "get involved" in a charity - to receive newsletter, to feel proud of my choice - and to have actually sought out the charity to give money to - rather than waiting for them to come to me.

So get started today. Make a list of the things you really care about passionately, and find the ideal charity to support that. Then get involved, meet some great people and be prepared to start changing the world in your own little way.