Bielecki's cooperative quickly received work in tax consultancy. The opaque and often vague tax codes issued by the communist government confused state enterprise managers, who relied on Doradca to assist them in limiting their tax returns. The cooperative, using the many loopholes that existed in the tax code, gained expertise in raising individual salaries at state firms without raising tax liabilities. In 1987, Bielecki organized his employees to create software simulating various strategies on wage tax liabilities. The software became immensely popular with Poland's largest enterprises, who quickly purchased copies. By 1988, the government eased prohibitions on Western firms making joint ventures with Polish enterprises. With few consultancy firms in place, and fewer English-speaking Poles conversant in Western financial analysis, Doradca was well-placed to assist these new firms with Poland's tax and banking regulations. At the same time, Doradca, through the efforts of Bielecki, continued to assist in recruiting and employing underground Solidarity members. During that time, Bielecki was given the nickname "Little Black" () among Solidarity activists, supporters and trade unionists.