Ehrmann mainly invests through Hong Kong and the US, and he does not invest in A shares, although he keeps an eye on the latter so as to keep tabs on the best companies in China in various sectors. Ehrmann says some technical issues need to be tidied up in the A-share market, such as with tax, before investors put their money into it.

Though he says ignorance about China is still on a par to what it was 15 years ago, the obvious difference is that it is not for want of information on the subject.

"You work out what is important over time," he says.

For instance, power and energy use are good indicators of growth when the economy is driven by investment, but not necessarily so during the transition period when there is greater efficiency.

He spends little time reading newspapers, he says, opting for weightier matter. He says he has read "China 2030" several times, a 468-page report published in February by the World Bank and the Development Research Center of the State Council, a government think tank. He also reads high-level government documents, such as the 12th Five-Year Plan (2011-15), and talks with the management teams of the companies he invests in. He travels to China three or four times a year.

There are two extremes in China's corporate governance, he says. Many state-owned companies that provide medical care and education for their staff still think they do not have to make a profit. Family companies, driven by entrepreneurship, are more efficient and competitive, he says, but they still think their business belongs to their family, not the public.

What Ehrmann does is to find the companies in between, companies that hire good professionals, make profits and pay dividends.

"We prefer single-focus companies (where) management have all their attention in the business they are doing."

Investing in China can be frustrating. "It is frustrating when investors do not seem to understand, and companies let you down."

He recently talked with what he regarded as a good chemical company but decided against investing because it wanted to buy property, in addition to the two private jets it has. If a company does not stay focused, he will not hesitate to sell shares and walk away, he says.

"There is no point waiting. We will just leave."

That is like life in general, he says. In solving problems you grow, so not all problems are bad. "What defines you as a person is often how you deal with them. In a transition period, that is what you do."

China continues to fascinate him, and with his long experience in investing in emerging markets he does not fear countries that are not perfect, he says, as long as they are moving in the right direction.

"What could be more fun than studying a country whose every action has a world impact, and the world knows too little about it?"

Three decades into his career as a fund manager, he says he still enjoys it. His father is an industrialist who builds factories and sells products, and he has to wait five years to see whether his decisions are right.

Ehrmann became involved in the US equity market when the British financial market was relatively closed, and he focused on mid-cap growth companies. In his job, he can build strategies and plan the future through the stocks he chooses, essentially doing what his father does, he says. But he does not have to wait for five years and sack thousands of people if he makes a mistake; he can simply dump poor shares.

Nevertheless, how the shares are doing is a daily preoccupation for him. Likewise, his father can fret about business, he says, but at least he knows that there are machines there to make things that people will buy.

Ehrmann says another good thing about his job is the opportunity it gives him to deal with interesting people. He recalls that in 1984, when he was 23, he sat in the same room with Gordon Moore, co-founder of the computer chip maker Intel. More recently he met Jack Ma, founder of Alibaba, China's biggest e-commerce platform. If such companies make it to the top in China, transforming its industry, they are going to have a key role in shaping the world, he says.

diaoying@chinadaily.com.cn