On the main streets they sell shoes, bags, clothes, electrical equipment. In residential areas it is small amounts of food or individual cigarettes arranged in delicate patterns to disguise the fact that the seller has not much stock.
"It's great," a World Bank official told me, "economic activity on such a scale has to be a good sign." He would say that. Street trading sprang up in 1993 soon after Zambia's new government brought in an economic- reform programme inspired by the World Bank and IMF. In Zambia today no one seems to make, mine or grow anything: they are all selling to one another.
When you look closely at the stalls you find they are selling identical produce at identical prices. And business is poor. "You can go all day without selling," said a trader who travels to Zimbabwe by bus to buy stock. "That's terrible, because you have to sell at knockdown prices, so turnover is crucial."
At the poorer end of the scale the shanty trader can end up eating unbought stock, leaving no money to replenish it. "I used to sell tomatoes but too much didn't sell and went bad. So I switched to this," said Matilda Phiria, a widow. She now smashes rock into gravel in the hope of making a little money selling it to a builder.
A diplomat from one of the nations to which Zambia owes a large chunk of its foreign debt said: "It's all trade, and it's good. If maize passes through Zambia in transit from South Africa to the Congo that's a worthwhile trade. It creates jobs."
Things look different to the hungry of the Copper Belt who see the cereal pass by on its way to the Congo, where it sells at a good price. The market is working perfectly in this, matching supply to demand, taking the food to where there is the money to pay for it. The shame is that ordinary Zambians do not have the cash, nor do their businessmen. Part of the reform demanded by the West is large-scale privatisation. Some 215 of the 315 state businesses have been sold in a programme which the World Bank sees as "the wonder of Africa".
But Zambian entrepreneurs cannot afford to buy. Most of the businesses have been sold to foreigners. (If you have the cash, try the Zambian national grid, was the tip of one Westerner out there to prepare it for sale).
The trouble is that the Zambian national interest and that of foreign capital sometimes do not coincide. When a big hotel was privatised in Livingstone, it was bought by a rival Zimbabwean hotel across the river and promptly shut down. Something similar appears to be happening with the nation's main fertiliser factory at Kafue.
But foreign money has the Zambians over a barrel. That much is clear over the sale of the nationalised copper industry, whose South African and Canadian buyers, having initialled a deal, are currently trying to renegotiate a much harder bargain with the government. Trade may be the lifeblood of any nation, but it does nothing to redress those injustices which grow from an imbalance in power.