Old and new: to ensure the Chinese economy was not engulfed by the global malaise, the government injected huge sums into public spending projects Photo: GETTY  Fund managers often talk about the "themes" that excite them and how they work those ideas into their investments. China is full of exciting opportunities but I would not call it a theme. It is much bigger than that; it is the most important thing going on in the world this decade and the next.  You might find it surprising that the manager of a UK equity growth fund is as interested in China as the state of British banks and whether M&S will increase its dividend. But what is happening in China is as important to your investments as what happens here. Not to have a view on it in your portfolio would be a huge mistake.  China is a long way away; culturally and geographically. As a result, some investors here often dismiss China as something happening to someone else. Their scepticism about the scale of activity means they enjoy belittling this emerging economic superpower. The fact is, without China propping it up, the global economy would be in a worse state than it currently is. It matters to us all whether or not Chinese growth is sustainable.  I have visited China several times in the past few years and my trip in June demonstrated once more China's glorious ability to astound; even after the financial crisis.  The main shopping street of any one of a hundred large Chinese cities at 10pm on a Tuesday is virtually indistinguishable from Oxford Street on a busy Saturday afternoon – perhaps with more neon!  China is a reason to be optimistic about the outlook for world growth. Government finances are healthy and consumers are spending as confidence returns. Chinese people, unlike us, are not encumbered by a decade of over-borrowing. Things may be bad in the West, but it's not often that a billion people go through an industrial revolution. In fact, it's never happened before.  To ensure the Chinese economy was not engulfed by the global malaise, the Chinese government injected huge sums of money into public spending projects. Apart from being the catalyst for a stock market recovery last autumn, you can see its impact everywhere. For example, China Railways has been adding track to the network at about 1,000 kilometres a year. This will rise to 10,000 kilometres per year by 2012. To put that into context, the whole UK network is just 16,000 kilometres.  There are critics of this ''overdevelopment''. You can drive along empty eight-lane motorways and wander shopping malls with more staff than customers. Countless suburbs are being developed and redeveloped to provide larger flats and to accommodate the 400 million people moving from rural to urban areas.  I visited Shenyang in north-east China, a city you might not have heard of despite having a population similar to that of Greater London. In just one corner of this one city, there is a construction site of two housing developments with a combined floorspace similar to the whole of London's Docklands.  Rather than see this as a bubble waiting to burst, I see the longer-term opportunity. Properties in Shenyang are selling faster this year than last. Before long the aspirational emergent middle class of China's mushrooming cities will be able to afford cars to fill the roads and to shop in the malls. Urbanisation begets economic growth.  In a broad sense, Chinese growth is affecting asset prices, demand and supply in almost every global industry. More specifically, despite their ingenuity, capital and human resource, the Chinese still look to British companies for certain goods and services.  British technology and engineering is in demand. Longer term, local competition will catch up. Therefore, investors' challenge is to find companies with whom the Chinese will never be able to compete. London's mining sector is an obvious beneficiary of China's lack of natural resources. Less obvious strong positions are those held by Western brands. Diageo, maker of Johnnie Walker, and fashion label Burberry, enjoy premium status among Chinese consumers. It is their very ''un-Chinese-ness'' that creates opportunity.  I am realistic. Rampant growth creates imbalances. This is a long-term story and not without risk. So be careful not to become overexposed and ensure your investments are balanced against many other themes and ideas. However, I am consistently surprised by the failure of many people to appreciate and take advantage of China being the biggest thing to happen in the world economy for a century.  Tom Ewing is portfolio manager at Fidelity UK Growth Fund
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