Chinese companies investing in Africa get a bad rap. Beyond their alleged role of ensnaring recipient countries in debt, when it comes to their employment record a common accusation is that they employ mainly Chinese workers, depriving locals of potential jobs. When they do hire locally, critics say, they pay badly and offer little training.

That is certainly the view of many Europeans and Americans, including US officials who have painted a grim picture of Chinese companies’ rapacious practices. It is also a view echoed in Africa itself. Many a labourer in Nairobi or executive in Accra turns up their nose at the mention of Chinese business.

But is it true? Until now there was little way of knowing. Almost all the information was anecdotal. Few academic studies of any size or rigour had been conducted. Now, after four years of intensive fieldwork, that gap has been partially filled by the most comprehensive study of its type yet.