We organized business associations for the owner-managers of randomly selected young Chinese firms to study the effect of business networks on firm performance. We randomized 2,800 firms into small groups whose managers held monthly meetings for one year, and into a “no- meetings” control...

We combine data on trade, production, and input use to compute the value added content of trade for forty-two countries from 1970 to 2009. For the world, the ratio of value added to gross trade falls by ten to fifteen percentage points, with two-thirds of this decline in the last two decades....