Section 5(4) (nurse's holding power) of the Mental Health Act 1983 permits nurses of the 'prescribed class' to detain an informal inpatient. The patient must already be receiving treatment for mental disorder. The section lasts for up to 6 h. Section 5(4) is over 30 years old; however, there is relatively little literature exploring its use. Existing literature has limited itself to surveys and audits investigating: nurses' opinions of Section 5(4); nurses' knowledge of Section 5(4); and trends associated with the implementation of Section 5(4). The literature review suggests that what is known about the implementation of Section 5(4) is incomplete. For example, there are no accounts of how and why the holding power is implemented from both a nursing and patient perspective. Section 5(4) (nurse's holding power) of the Mental Health Act 1983 in England and Wales accounts for 10% (n = 1714) of all detentions after admission to hospital. It is followed by further detention in 66% of cases and may require nurses to restrain, seclude or closely observe the patient to prevent them harming themselves and/or others. To conduct a literature review of empirical articles concerning the implementation of Section 5(4), a literature search was undertaken in ASSIA, British Nursing Index, Medline, PsycINFO and Lawtel, using a combination of the keywords 'Section 5(4)', 'nurse's holding powers', 'holding powers', 'Mental Health Act 1983', 'MHA', 'compulsory detention', 'formal detention', 'emergency psychiatric interventions', 'containment interventions' and 'involuntary commitment'. Twenty-five articles were included in the review. Existing literature has focused on surveys and audits investigating: nurses' opinions of Section 5(4); nurses' knowledge of Section 5(4); and trends associated with the implementation of Section 5(4). While this literature has provided some insights into the implementation of Section 5(4), it is clear that what is known about its use is incomplete. Further research is required to examine a number of areas, for example, how and why the section is implemented.