This document comprises Deliverable D2.1 (“Case Study Manual”) of the COST Action NERO, CA22164. The overarching objective of the NERO Case Study Manual (CSM) is to lay the groundwork for the systematic analysis of past wildfire events, using established methods and tools while encouraging the integration of new techniques. The manual introduces guiding principles that should be considered in the design and implementation of high-quality wildfire case studies while recognizing that some flexibility is needed to accommodate the unique characteristics of each event.