The growing gap between rich and poor, within nations and between them, is an inevitable consequence of the way we've chosen to arrange the economy. Over the last 30 years, a politically-driven programme of economic liberalisation has tied economic success (as measured by GDP growth) to growing inequality. More people may be richer than ever before, but many more people are poorer; both are the inevitable consequence of economic advance under the current model.
Mark is completely right. To talk about reducing poverty while maintaining the current economic system is like talking about reducing one's weight while living off a diet of chocolate bars and ice cream.
The trouble is that the powers that be have determined that neo-liberalism is the only economic model allowed in today's world. After communism was destroyed they have set about destroying Europe's mixed economy model too. This is what the 'reform' of Europe's economies means. They won't be happy until the whole of the world has no publicly owned enterprises at all and progressive taxation is replaced by regressive indirect taxes or flat taxes. If we are ever going to make any impact in reducing poverty, we urgently need to replace the flawed neo-liberal model and return to the policies which, in the post-war period, helped bring about the fastest reduction in inequality in history. There really is no other way.