Background. Unplanned readmissions of recently discharged patients impose a significant burden on hospitals with limited bed capacity. Deficiencies in discharge processes contribute to such readmissions, which have prompted experimentation with multiple types of peridischarge interventions.Objective. To determine the relative efficacy of peridischarge interventions categorised into two groups: (1) single component interventions (sole or predominant) implemented either before or after discharge; and (2) integrated multicomponent interventions which have pre-and postdischarge elements.Design. Systematic metareview of controlled trials. Data collection. Search of four electronic databases for controlled trials or systematic reviews of trials published between January 1990 and April 2009 that reported effects on readmissions.Data synthesis. Among single-component interventions, only four (intense self-management and transition coaching of high-risk patients and nurse home visits and telephone support of patients with heart failure) were effective in reducing readmissions. Multicomponent interventions that featured early assessment of discharge needs, enhanced patient (and caregiver) education and counselling, and early postdischarge follow-up of high-risk patients were associated with evidence of benefit, especially in populations of older patients and those with heart failure.Conclusion. Peridischarge interventions are highly heterogenous and reported outcomes show considerable variation. However, multicomponent interventions targeted at high-risk populations that include pre-and postdischarge elements seem to be more effective in reducing readmissions than most single-component interventions, which do not span the hospitalcommunity interface.What is known about this topic? Unplanned readmissions within 30 days of hospital discharge are common and may reflect deficiencies in discharge processes. Various peridischarge interventions have been evaluated, mostly single-component interventions that occur either before or after discharge, but failing to yield consistent evidence of benefit in reducing readmissions. More recent trials have assessed multicomponent interventions which involve pre-and postdischarge periods, but no formal review of such studies has been undertaken. What does this paper add? With the exception of intense self-management and transition coaching of high-risk patients, and nurse home visits and telephonic support for patients with heart failure, single-component interventions were ineffective in reducing readmissions. Multicomponent interventions demonstrated evidence of benefit in reducing readmissions by as much as 28%, with best results achieved in populations of older patients and those with heart failure. What are the implications for practitioners and managers? Hospital clinicians and managers should critically review and, where appropriate, modify their current discharge processes in accordance with these findings and negotiate the extra funding and personnel required to allow succ...