The Bulgarian public procurement market constituted 9% of national GDP on average from 2009 – 2013, which is lower than the EU average. Public procurement has been particularly important for the construction sector in the country, with approximately a third of total sector turnover deriving from public procurement in 2013. Since the onset of the economic crisis in 2008 the survival of the construction sector in Bulgaria has essentially hinged on public procurement, coming mostly from EU funds. This concentration of market power in the hands of the public administration, coupled with a history of lack of effectiveness, integrity and control, and persistent structural governance deficiencies imply significant corruption risks. Although the legal framework has continuously improved, it is subject to too frequent changes to ensure proper implementation.The firm-level analysis of the public procurement contracts awarded to the top 40 construction companies included in the paper, confirms the trend of concentration of the construction sector. The data does not confidently detect a specific type of favouritism but corruption risks are detected in specific cases, especially involving large-scale construction projects in the infrastructure and energy sectors. Anecdotal evidence abounds that powerful private operators exert pressure on the public administration to channel public procurement to major companies, linked either legally and/or through circles of influence to them.