Protocol 16 ECHR will provide for an extension of the advisory jurisdiction of the European Court of Human Rights (ECtHR), enabling highest national courts to request advisory opinions on questions of principle concerning the interpretation of the European Convention on Human Rights (ECHR) or its protocols. This extension of the ECtHR's advisory jurisdiction aims to achieve two goals: a reduction in the ECtHR's excessive docket, and the enhancement of dialogue between the ECtHR and (highest) national courts. While the aims of this reform initiative are laudable, we argue that Protocol 16 is likely to fail to achieve its objectives. Our analysis suggests that rather than facilitating the Court's adjudicatory function, extended advisory jurisdiction has the potential to impact on the Court's constitutionalist function in a manner that can be better achieved through the Court's contentious cases. The burden that this procedure will place on the Court's already overstretched resources would risk delays to contentious cases and potentially undermine judicial comity should requests for advisory opinions be declined. Furthermore, evidence of ‘constructive’ dialogue between highest national courts and the ECtHR is emerging in contentious cases without the need for a reformed advisory opinions mechanism. Rather than achieving its objectives, Protocol 16 risks exacerbating the Court's backlog and nullifying the positive effects of advisory opinions on dialogue.