Data on Chinese business activity in North Korea have hitherto been scarce and fragmentary. A recent report by Drew Thompson, the director of China studies at a US think-tank, the Nixon Center, shines much-needed light on the subject. So far the scale does not seem to be large. In 2003-09 Chinese investment in North Korea totalled only US$98.3m, far less than that in any other neighbouring state-South Korea received US$1.2bn. Nor is it very successful: North Korea is described as "a particularly difficult environment for Chinese investors due to rent-seeking, poor infrastructure and the oppressive political environment".

The majority of Chinese investors in the North are privately owned companies and state-owned enterprises under the control of provincial, prefecture and municipal authorities. Only four out of 138 were companies controlled by the Chinese central government. China's largest private firms were largely notable by their absence: only two of China's top 100 companies have invested in North Korea, and they are both steel-makers. By sector, mining and consumer goods are prominent. Of the 138 joint ventures established between 1997 and August 2010, 41% were in extractive industries and 38% in light industry, with 8% in heavy industry and 13% in services. Geographically, the two Chinese provinces that border North Korea predominate, as 28% of Chinese firms involved in these joint ventures come from Jilin and 34% from Liaoning.

The overall sense is that so far these projects are relatively small in scale. But Chinese investment in North Korea could grow significantly in the future if fresh infrastructure plans come to fruition-as some past projects, for instance, that to upgrade the Hunchun-Rajin transport corridor, have not. There has been some suggestion recently that the Chinese government has put pressure on state-owned banks to support increased investment in the North by Chinese companies. The tough business environment, volatile political outlook and ambivalent position of many of the larger Chinese companies involved in the projects may nevertheless mean that both the scale and impact of Chinese foreign investment will fall short of the billions of US dollars that are often talked of.