This book constitutes revised selected papers from the 9th Brazilian Workshop on Agile Methods, WBMA 2018, held in Campinas, Brazil, in October 2018. The 6 full and 1 short papers presented in this volume were carefully reviewed and selected from 18 submissions.Accepted papers in this edition present empirical results and literature reviews on agile requirements validation in Brazilian software development companies; a survey on Brazilian software processes about to be agile or not; an evaluation of an agile maturity model; strategies to increase customer value in agile software development; an agile development environment and scrum in a strongly hierarchical organization.