On March 31, CMS released special edition MLN Mattersarticle SE1607 regarding new enforcement editing requirements for the Medicare Benefit Policy Manual (Internet-Only Manual 100-02), Chapter 6, section 70.3, which describes coverage and billing of Partial Hospitalization Program (PHP) services. This guidance is likely due to the significant problems with PHP service claims and coding highlighted in the 2016 proposed and final OPPS rules. This guidance is effective for PHP services furnished on or after July 1.