 As well, in March 2018, the IPCC held a conference in preparation for a special report on cities and climate change in the seventh assessment cycle.Since its inception, the IPCC had also published over a dozen Special Reports which are included in the ARs.The Special report also includes a Summary for policymakers providing an "assessment of a specific issue and generally follow the same structure as a volume of an Assessment Report and Methodology Reports which are "materials that provide practical guidelines for the preparation of greenhouse gas inventories."