Abstract
In the paper the author makes a classification of the Construction Sector companies that are listed on the Warsaw Stock Exchange. The classification is made with a view to identify those companies whose financial standing in the years of study (2007, 2009 and 2011) was good or bad from the point of view of several selected ratios. The classification is based on the inquiry into the stability of final diagnoses of the companies’ financial standing. The final diagnoses were founded on the median from partial diagnoses which had been created in the course of a two-element diagnostic process where the real values of the companies’ financial indices were compared with theoretical and empirical norms.