WARSAW -- To rebuild Eastern Europe, the next step is to get as many business enterprises as possible into private ownership -- and to do it rapidly. The old machinery of central planning has collapsed along with the Communist parties that ran it, and most of these countries' factories are now drifting. To get performance up, the new governments have to put them into the hands of people with the authority to make decisions and the incentives to make the right ones.

Poland is moving fast, and its success or failure is going to have a powerful influence throughout the rest of Eastern Europe. The former East Germany is a special case, with the massive resources of its western cousin to support it. Czechoslovakia and Hungary are procrastinating. Of all the countries emerging from communism, Poland is the largest and most courageous -- the test case.

There were about 8,000 state enterprises in Poland when the Communist regime collapsed last year, and so far only eight have been put under private ownership. Lech Walesa, in his successful campaign for the presidency, promised a dramatic acceleration. But that won't be simple. One official described it as selling "property of unknown value to people with no money to buy."

The most promising place to start is not with the largest and most visible enterprises but with the small ones, explains Janusz Lewandowski, the newly appointed minister for ownership changes. Of the 8,000, some 3,500 have fewer than 100 employees and are small enough that they might be sold to individual Polish buyers, the kind of people who are willing to stake their savings and mortgage their houses to go into business for themselves.

Another 2,000 enterprises are suitable for municipal ownership, and most have already been turned over to local governments. Some are utilities. Some are local shops that the cities are now leasing to private operators.

About 2,000 are candidates to be broken up and their pieces sold, perhaps to foreign investors, or leased or turned over to employee-run corporations. That leaves about 500 hard cases -- most of them big industrial operations, often set up to feed a Soviet market that is now collapsing.

One proposal is to distribute at least some of the ownership to the general public through vouchers. The idea has the obvious political appeal of acknowledging the citizens' contribution of their labor in building the economy that is now being sold off, but the actual distribution would be extremely complex.

It would be unfair, for example, simply to give people shares in the enterprises where they work, since some of those factories will be profitable and others will fail. Lewandowski would prefer to give all citizens shares in mutual funds that in turn would hold the shares of many new companies. But that assumes a sophisticated financial market capable of evaluating and trading shares -- and that, along with much else, has still to be organized. The government is to decide within the next month whether and how to proceed with the voucher concept.

The economic strategists are very much aware of the danger of allowing ownership to become so widely diffused that the new owners have no effective control over management and companies continue to slide. A solution might be to bring the mutual funds and pension funds into active management.

One great danger in this process, Lewandowski acknowledges, is the possibility of an epidemic of failures among the new owners. There is a severe shortage of capital needed to reorganize and equip these enterprises. Very little foreign investment has come into the country so far, and the book value of the enterprises to be sold is 10 times the total savings in the country -- the pool of domestic capital available to buy them. Another crucial shortage is in the executive skill and experience to manage large businesses in a modern market economy.

But if the troubles of the big enterprises are severe, it is also true that the Polish private economy is coming alive from the bottom up. There are now some 30,000 shops, previously state-owned, in private ownership. That doesn't count the vast variety of peddlers and vendors that line the main streets of Polish cities. By one estimate there are now more than 1 million private businesses in Poland, a number that has tripled over the past year.

Four-fifths of Polish manufacturing is still in the public sector. But in services, according to Leszek Balcerowicz, minister of finance, about a third of all enterprises are now privately owned. The shift has been particularly rapid in retail trade, in which about 5 percent of the volume of sales ran through privately owned business a year ago. Now it's about 40 percent.

Poland leaves a visitor with an unexpectedly strong impression of energy and growth. Last year its exports to the West rose by a third, a performance that astonished the Poles themselves. Poland used to sell the West mostly commodities such as coal and agricultural products. Now its exports are predominantly chemicals and manufactured goods, a sign of rising strength.

The men running Poland's economic policy are intensely aware that more than money depends on their success. Growing prosperity and an emerging class of independent traders, managers and owners are going to be indispensable to stable democracy. Economic policy always turns out to involve a lot more than economics. The writer is a member of the editorial page staff.