We are about to witness an almost unprecedented centralized partnership audit regime that takes full effect for taxable years starting on or after January 1, 2018, as adopted in late 2015 by Section 1101 of the Bipartisan Budget Act (BBA), with some minor modifications shortly after enactment. The new regime represents a break with the principle, long thought to be axiomatic, that a partnership always passes through income tax liability to the partners and is not itself taxable. In general, the legislation will permit the IRS on audit to assess and collect income taxes at the partnership level.