This article provides for a critical examination of the principal purposes test (PPT) of article 29(9) of the 2017 OECD Model Income Tax Convention on Income and on Capital. The focus is on the second part of the PPT, which allows for the granting of treaty benefits in the presence of a tax avoidance motive if that would be in accordance with the object and purpose of the relevant provisions of the OECD Model. Questions are raised as to how exactly the object and purpose are determined, the consistency of the relevant parts of the Commentary on the 2017 OECD Model is discussed, and the Examples that purport to clarify the application of the PPT are critically reviewed. Finally, an effort is made to come to a sensible and workable synthesis of the various aspects of the PPT, including the “nexus” part and the “abusive transactions” part thereof, which will be addressed in some detail, and a concept is explored to extend the multilateral approach taken with respect to the minimum standard of the BEPS Action 6 Final Report to the nexus part of the PPT.