Probably at the same time, regional associations, the so-called “hui-kuan" originated.  Such associations united people from one city or one area who lived in another city.  People of different trades, but mainly businessmen, came together under elected chiefs and councillors.  Sometimes, such regional associations could function as pressure groups, especially as they were usually financially stronger than the guilds.  They often owned city property or farm land.  Not all merchants, however, were so organized.  Although merchants remained under humiliating restrictions as to the colour and material of their dress and the prohibition to ride a horse, they could more often circumvent such restrictions and in general had much more freedom in this epoch.

Trade, including overseas trade, developed greatly from now on.  Soon we find in the coastal ports a special office which handled custom and registration affairs, supplied interpreters for foreigners, received them officially and gave good-bye dinners when they left.  Down to the thirteenth century, most of this overseas trade was still in the hands of foreigners, mainly Indians.  Entrepreneurs hired ships, if they were not ship-owners, hired trained merchants who in turn hired sailors mainly from the South-East Asian countries, and sold their own merchandise as well as took goods on commission.  Wealthy Chinese gentry families invested money in such foreign enterprises and in some cases even gave their daughters in marriage to foreigners in order to profit from this business.

We also see an emergence of industry from the eleventh century on.  We find men who were running almost monopolistic enterprises, such as preparing charcoal for iron production and producing iron and steel at the same time; some of these men had several factories, operating under hired and qualified managers with more than 500 labourers.  We find beginnings of a labour legislation and the first strikes (A.D. 782 the first strike of merchants in the capital; 1601 first strike of textile workers).

Some of these labourers were so-called “vagrants”, farmers who had secretly left their land or their landlord’s land for various reasons, and had shifted to other regions where they did not register and thus did not pay taxes.  Entrepreneurs liked to hire them for industries outside the towns where supervision by the government was not so strong; naturally, these “vagrants” were completely at the mercy of their employers.

Since c. 780 the economy can again be called a money economy; more and more taxes were imposed in form of money instead of in kind.  This pressure forced farmers out of the land and into the cities in order to earn there the cash they needed for their tax payments.  These men provided the labour force for industries, and this in turn led to the strong growth of the cities, especially in Central China where trade and industries developed most.

Wealthy people not only invested in industrial enterprises, but also began to make heavy investments in agriculture in the vicinity of cities in order to increase production and thus income.  We find men who drained lakes in order to create fields below the water level for easy irrigation; others made floating fields on lakes and avoided land tax payments; still others combined pig and fish breeding in one operation.