In July 2017, the OECD Committee on Fiscal Affaires released the draft contents of the 2017 update to the OECD Model Tax Convention (OECD MC). The draft contents most likely will find their way into the final version of the OECD MC and the Commentary 2017. The update includes all tax treaty-related measures of the BEPS package, including changes of the concept of permanent establishments (PE) as proposed in BEPS Action 7, as well as new guidelines for the interpretation and application of Art 5 OECD MC recorded in the corresponding Commentary. Changes to Art 5 OECD MC will be introduced into the tax treaty network through the Multilateral Instrument, which Austria signed on June 7^th, 2017, in Paris. Stefan Bendlinger takes a closer look at engineering and construction PEs and examines the consequences of the revised provisions for enterprises working on building sites, construction and installation projects.