The Recommendations for Specialized Nutritional Support in Critically-Ill patients were drafted by the Metabolism and Nutrition Working Group of the Spanish Society of Intensive Care Medicine and Coronary Units (SEMICYUC) in 2005. Given the time elapsed since then, these recommendations have been reviewed and updated as a Consensus Document in collaboration with the Spanish Society of Parenteral and Enteral Nutrition (SENPE). The primary aim of these Recommendations was to evaluate the best available scientific evidence for the indications of specialized nutritional and metabolic support in critically-ill patients. The Recommendations have been formulated by an expert panel with broad experience in nutritional and metabolic support in critically-ill patients and were drafted between October 2009 and March 2011. The studies analyzed encompassed metaanalyses, randomized clinical trials, observational studies, systematic reviews and updates relating to critically-ill adults in MEDLINE from 1966 to 2010, EMBASE reviews from 1991 to 2010 and the Cochrane Database of Systematic Reviews up to 2010. The methodological criteria selected were those established in the Scottish Intercollegiate Guidelines Network and the Agency for Health Care policy and Research, as well as those of the Jadad Quality Scale. Adjustment for the level of evidence and grade of recommendation was performed following the proposal of the GRADE group (Grading of Recommendations Assessment, Development and Evaluation Working Group). Sixteen pathological scenarios were selected and each of them was developed by groups of three experts. A feedback system was established with the five members of the Editorial Committee and with the entire Working Group. All discrepancies were discussed and consensus was reached over several meetings, with special emphasis placed on reviewing the levels of evidence and grades of recommendation. The Editorial Committee made the final adjustments before the document was approved by all the members of the Working Group. Finally, the document was submitted to the Scientific Committees of the two Societies participating in the Consensus for final approval. The present Recommendations aim to serve as a guide for clinicians involved in the management and treatment of critically-ill patients and for any specialists interested in the nutritional treatment of hospitalized patients.