There is ongoing debate in the UK as to the place of coercion and compulsion in community mental health care. Recent changes in service provision and amendments to the Mental Health Act in England and Wales have increased the scope for compulsion in the community. This has intensified the debate revealing fault lines in the psychiatric and legal professions. Despite powerful arguments from all sides there is little empirical evidence to inform this debate at a clinical or a theoretical level. This review utilizes evidence from articles in peer reviewed journals. Papers were identified from electronic databases, the authors' databases of relevant literature and personal correspondence with experts in the field. The evidence base is relatively small but is expanding. It has been demonstrated that informal coercion is common in USA mental health services and can be experienced negatively by patients. There is evidence that powers of compulsion in community mental health care are used frequently when available and their availability is generally seen as positive by clinicians when practice becomes embedded. The evidence for the effectiveness of compulsion in community mental health care is patchy and conflicting, with randomized or other trials failing to show significant benefits overall even if secondary analyses may suggest positive outcomes in some subgroups. There are widespread regional and international differences in the use of community compulsion. Research examining treatment pressures (or 'leverage') and the subjective patient experience of them appears to be expanding and is increasing our awareness and understanding of these complex issues. There is an urgent need for evidence regarding the usefulness and acceptability of compulsion in the community now that powers have been made available. Trials of the effectiveness of compulsion are needed as is qualitative work examining the experiences of those involved in the use of such orders. These are needed to help clinicians utilize the powers available to them in an informed and judicious fashion and to ensure adequate training.