The development of practice parameters for intravenous analgesia and sedation for adult patients in the intensive care unit (ICU) setting for the purpose of guiding clinical practice. A task force of more than 40 experts in disciplines related to the use of analgesic and sedative agents in the ICU was convened from the membership of the American College of Critical Care Medicine (ACCM) and the Society of Critical Care Medicine (SCCM). The task force members provided the personal experience and determined the published literature (MEDLINE articles, textbooks, pharmacopeias, etc.) from which consensus would be sought. Published literature was reviewed and classified into one of four predetermined categories, according to study design and scientific value. The task force met several times as a whole, and numerous times in smaller groups by teleconference, over a 1-yr period to identify the pertinent literature and arrive at consensus recommendations for the whole task force to discuss. Consideration was given to the relationship between the weight of scientific information and the experts' viewpoints. Over the next year, draft documents were composed by a task force steering committee and debated by the task force members until consensus was reached by nominal group process. The task force draft was then reviewed, assessed, and edited by the Board of Regents of the ACCM. After steering committee approval, the draft document was reviewed and approved by the SCCM Council. To facilitate rapid communication of the six recommendations contained within the complete and unabridged practice parameter document, an executive summary was prepared for publication by the ACCM Board of Regents, and this executive summary was approved by the task force steering committee and the SCCM Executive Council. A consensus of experts provided six recommendations with supporting data for intravenous analgesia and sedation in the ICU setting: a) morphine sulfate is the preferred analgesic agent for critically ill patients; b) fentanyl is the preferred analgesic agent for critically ill patients with hemodynamic instability, for patients manifesting symptoms of histamine release with morphine, or morphine allergy; c) hydromorphone can serve as an acceptable alternative to morphine; d) midazolam or propofol are the preferred agents only for the short-term (< 24 hrs) treatment of anxiety in the critically ill adult; e) lorazepam is the preferred agent for the prolonged treatment of anxiety in the critically ill adult; f) haloperidol is the preferred agent for the treatment of delirium in the critically ill adult. This executive summary selectively presents supporting information and is not intended as a substitute for the complete document.