The workers at the IMPA aluminum plant here all can remember when their company was privately owned, and a few veterans even recall when it was the property of the state. But these days, as a result of the worst economic crisis in the country's history, it is the workers themselves who are the factory's stockholders and managers.

When the economy collapsed here 18 months ago, the situation was so bad that the owners of many factories simply shut their doors and walked away, in most cases owing their employees months and months of back pay. Rather than accept that situation, workers -- backed by neighborhood associations and left-wing groups enamored with the idea of ''people's capitalism'' -- have sometimes been able to persuade bankruptcy courts to let them take over the company's assets.

''The only boss here now is the customer,'' said Plácido Peñarieta, one of nine employees at the Chilavert Artes Gráficas cooperative, which prints art books and posters, calendars and concert programs. ''We've learned to depend on ourselves and nobody else, because we know that our success or failure depends on what we, and we alone, do.''

Across this nation of 37 million people, at least 160 factories employing an estimated 10,000 people are now being run as cooperatives by their employees, ranging from a tractor factory in Córdoba to a tile and ceramics plant in Patagonia. But the largest concentration is here in the capital and its suburbs, where the nucleus of the country's industrial production is situated.