The political debate on the introduction of a national minimum wages is typically concerned about its employment effect on those who are directly affected by a binding minimum wage. Other non-intended effects of minimum wages on the employment and wage structure that affect also qualified workers who are not directly affected by a binding minimum wage are much less in the focus of both research and politics. In Germany, a legal minimum wage was introduced to the roofing sector in 1997 and provides us with the opportunity to fill this empirical gap. The aim of the project thus is to identify the causal effects that the minimum wage has on the employment structure and the wage structure with the focus being on the indirect effects of the minimum wage on qualified workers. For the proposed analyses, matched employer-employee data are available that allow for such an in-depth analysis.