The second edition of this text provides an expanded and comprehensive exploration of adult surgical critical care relevant for resource-replete and resource-constrained acute care settings. It can be used to review complex critical illness or injury topics in surgical patients, as a reference tool, a resource for board examination preparation, or as a guide for program development. Focused on the surgical patient, this text leverages a structured approach that includes key points, evidence-based management, and critical care principles underpinned by new knowledge discovery. Each chapter identifies controversies as well as adaptations for resource-constrained settings, and the international authorship underscores the global applicability of this work. Novel topics for the second edition include caring for the neurodiverse patient, the role of disordered lymphatic flow, deresuscitation, vascular pathologies, management of complex intra-abdominal surgery patients, the role of the microbiome in surgical critical care, obstetric and gynecologic critical care, organ donor management, as well as ethical elements of multicultural care. The text is written with an expectation that the reader possesses a foundation in critical care pathophysiology and clinical practices acquired during parent discipline training. Organized into organ system-based sections, each section contains several chapters addressing relevant disorders, monitoring and treatment modalities, and outcomes.  Sections are guided by expert Section Editors who are leaders within their respective fields. Principles of Adult Surgical Critical Care, Second Edition will be of use to intensivists caring for surgical patients regardless of parent training domain. Additionally, this work is intended to be used by surgical critical care fellowship trainees as well as advanced practice providers such as nurse practitioners and physician assistants who provide care in ICUs and emergency departments alike.