The use of selective decontamination of the digestive tract (SDD) remains controversial despite several large randomised-controlled trials and meta-analyses. A postal survey of intensive care units in the United Kingdom was conducted to document current use of SDD, and to identify factors influencing this practice. The response rate was 71%. The vast majority (182 units, 95%) do not use SDD mainly because practising clinicians do not believe it works or that there is not enough evidence (51%), and because of concerns about antibiotic resistance (47%). Of the 10 units using SDD, three apply it to all intubated patients and five do not use intravenous antibiotics in their protocol.