The mission of the Clinical Core is to provide the personnel, facilities, and organizational structure necessary to generate the clinical database and patient specimens for projects 1, 2, 3 and 4. The resources will support individual protocols within the Center, facilitate interactions between investigators, and provide a cohesive framework to the formulation, execution, and data analysis of clinical research projects. The clinical protocol is designed to approximate the best available strategies for diagnostic assessment nd therapy of sepsis induced acute lung injury (ALI) and adult respiratory distress syndrome (ARDS). The specific aims are: 1. To manage the clinical studies involving patients with sepsis-induced acute lung injury and ARDS. . Identify eligible patients . Obtain informed consent and enroll patients . Collect clinical data to provide complete characterization of the patients' clinical course. . Stratify severity of illness upon enrollment into the study with APACHE III and the Logistic Organ Dysfunction core (LODS) . Further stratify severity of illness daily with APACHE III and the LODS. . Provide a protocol to insure that patient care is standardized. 2. To procure tissue and cells for individual investigators. . Perform Ballard catheter bronchoalveolar lavage (BAL) in patients with acute lung injury and ARDS and in ventilated volunteers without lung injury. . Process the BAL fluid such that each project will be supplied with cell- free fluid an/or cell cells from these patients. 3. To provide data management and clinical severity indexing services to individual investigators. . Organize and manage the clinical database . Advice on study design, sample size calculations and selection of appropriate outcome variables . Fully characterize each patient's severity of illness upon enrollment and throughout clinical course to allow severity-specific interpretation of molecular biologic data . Assist with statistical applications and data analysis