This guidebook is the product of the Global WASH Cluster’s capacity building mapping project. This is one of a series of initiatives to assist the WASH cluster to better meet the needs of affected populations in emergency responses. The tools developed under this project are intended to: Assess the capacity of WASH actors to respond to emergencies; Identify capacity gaps to allow the development of a capacity building plan for the sector; Collate key WASH data in advance of emergencies to identify any likely WASH-related vulnerability in the case of an emergency response; Accelerate the need assessment process by the prior assembly of baseline date for particular areas and thereby speed up the design of the response, and; Support the collaborative identification of WASH vulnerabilities, capacity gaps and capacity building needs.