There is a realisation among many UNFCCC Parties who appreciate the value of a legally binding multilateral climate change regime (call them ‘appreciative Parties’) that the architecture of the Kyoto Protocol (KP) has to remain a cornerstone of any legally binding outcome of the current UN climate change negotiations. The problem is that there is no agreement among them on how this should be implemented. As witnessed in the recent submission by Australia and Norway, there are currently two alternatives being discussed: should one keep the Kyoto Protocol in more or less its current form, and complement it with a separate Protocol, covering the relevant key elements of the current negotiations under ‘Plan A’? Or should one start afresh with negotiating a comprehensive new instrument incorporating the key elements of the KP with ‘Plan B’? And what exactly should be the content and timetable of non-Kyoto commitments?