*Stealth of Nations*

The author is Robert Neuwirth and the subtitle is The Global Rise of the Informal Economy.  Excerpt:

The merchants here are Chinese.  But most of the customers, like Chief Arthur, are from Africa.  The trade is generally brisk — on Fridays it can be overwhelming — and it’s accompanied by what seems like a permanent sound track: the rasp of unspooling packing tape and the whir of currency counters.  Each box that leaves the market is heavily sheathed in plastic tape — to ensure a secure seal and to make it hard to tamper with.  And the economy here, as in almost all haphazard markets around the world, is cash-only.  All payments are made in yuan, and, as the largest denomination in Chinese currency is one hundred yuan — worth about $14 — people making big deals carry massive bundles of cash.  Chief Arthur, for instance, who was carrying a wad of four hundred hundred-dollar bills, had to convert them into almost three thousand hundred-yuan notes — a stack of bills large enough that he needed a briefcase or duffel bag to carry it around.

Much of this book draws from Nigeria, China, and Ciudad del Este in Paraguay.  Black markets are a well-worn topic, but I found a lot of the material here to be fresh and vital.  The book is due out in October.