This review provides an update of the evidence on the impact of physical activity (PA) interventions for patients in primary health care services. Sixteen studies published since 1999 are included. Twelve studies tested interventions of PA only and yielded good evidence that these can have a short-term (< 6 mths) impact upon behaviour. Four studies tested multiple risk factor interventions with a PA component, but the findings from these were inconclusive. There were insufficient studies to identify the attributes of effective interventions, but both brief and intensive single risk factor interventions produced short-term increases in PA. Little attention has been given in the research to the representativeness of study participants or intervention deliverers, or the potential for interventions to be transferred into routine service delivery. In light of current evidence, a reasonable approach for primary care practitioners is to undertake brief PA interventions with patients with health problems who could benefit from increased PA. Future research should pay greater attention to elements of study and intervention designs, including reach, adoption by practitioners and implementation within existing service structures, so that the public health potential of the findings can be realised.