This book provides clear guidance as to which neuroradiological findings in ill or injured patients should be immediately communicated by radiologists and trainees to the emergency room and referring physicians in order to facilitate key decisions and eliminate preventable errors. It offers a practical and illustrative approach that identifies what to look for and how to report it and describes the required follow-up and the most common differential diagnoses of the main critical findings in neuroradiology. The book is distinctive in being written from a “critical findings perspective”, which makes its content more practical and memorable than that of a standard Emergency Neuroradiology textbook. It also illustrates the value of developing algorithmic approaches to report and communicate critical findings based on lists. While the book will appeal to a broad and variable audience, it is especially addressed to radiology training programs and will be a “must read” for residents and fellows in training. Dr. Nunes received his training in Diagnostic Radiology at the Federal University of Sao Paulo followed by a 2-year Neuroradiology fellowship at Santa Casa de Misericordia de Sao Paulo. He also spent 1 year as a Visiting Scholar at the University of North Carolina at Chapel Hill. Currently, he is a practicing neuroradiologist at Fleury Medicina e Saude and Residency Program Coordinator at Santa Casa de Misericordia de Sao Paulo, Sao Paulo, Brazil. He is also a board member of Sociedade Paulista de Radiologia (SPR). Dr. Abello is a practicing neuroradiologist and a Professor of Radiology at the University del Valle in Cali, Colombia. She also spent 2 years as a Visiting Scholar at the University of North Carolina in Chapel Hill. Dr. Mauricio Castillo is Professor of Radiology, Chief and Program Director of Neuroradiology and a Fellow of the American College of Radiology. His areas of interest include pediatric neuroimaging, application of new imaging techniques and medical literature editing. Dr. Castillo is the author or co-author of over 550 original and invited articles and 17 books. In the past, he has served as a member of the editorial boards of 11 journals, an article reviewer for 27 journals and since 2007, has been editor-in-chief for the American Journal of Neuroradiology, the most important journal in clinical neuroimaging. Dr. Castillo has served as Secretary for the ASSR and has held several prominent positions in their Executive, Public Relations, Program Directors and Research Committees. He is a founding member of the American Society of Pediatric Neuroradiology (ASPNR) and served as Chair of its Research Committee and Education Committee. For the American Roentgen Ray Society (ARRS), he is Chair of the International Outreach committee and a member of the Executive Council. He chairs the Meetings Committee for the new ACR/ARRS initiative, where he is a member of five other committees.