The aim of this study was to describe the reasons for the use of restraint, the decision-making procedure for their use and the documentation of their use in Norwegian nursing home units. Structured interviews were carried out with the carers of 1362 patients in 160 regular nursing home units and 564 patients in 91 special care units for people with dementia. The reasons given for the use of restraint were to protect the patient or others, and to carry out necessary care or treatment. The main reason for the use of force or pressure in medical treatment was non-compliance of the patient. The nurse in charge (44%, n = 670) or a carer (13%, n = 201) most frequently decided that restraint should be used. In 65% (n = 892) of all the instances of restraint, no documentation was found in the patients' records. It was concluded that routines for quality assurance for decision-making about, and the documentation of, the use of restraint are lacking in Norwegian nursing homes.