BACKGROUND: It is crucial that research findings are implemented in general practice if high-quality care is to be achieved. Multifaceted interventions are usually assumed to be more effective than single interventions, but this hypothesis has yet to be tested for general practice care. This review evaluates the effectiveness of interventions in influencing the implementation of guidelines and adoption of innovations in general practice. A systematic literature study was carried out using MEDLINE searches for the period from January 1980 until June 1994, and 21 medical journals were searched manually. Randomized controlled trials and controlled before and after studies (with pre- and post-intervention measurements in all groups) were selected for the analysis. Clinical area, interventions used, methodological characteristics and effects on clinical behaviour were noted independently by two researchers using a standardized scoring form. Of 143 studies found, 61 were selected for the analysis, covering 86 intervention groups that could be compared with a control group without the intervention. Information transfer alone was effective in two out of 18 groups, whereas combinations of information transfer and learning through social influence or management support were effective in four out of eight and three out of seven groups respectively. Information linked to performance was effective in 10 out of 15 groups, but the combination of information transfer and information linked to performance was effective in only three out of 20 groups. Some, but not all, multifaceted interventions are effective in inducing change in general practice. Social influence and management support can improve the effectiveness of information transfer, but information linked to performance does not necessarily do so. The variation in the effectiveness of interventions needs further analysis.