The purpose of this trial is to evaluate the effectiveness of providing additional support in modifying lifestyles and in reducing population cardiovascular disease risk compared with usual primary prevention care. A prospective, individually randomised controlled trial design is used, within which groups of patients are clustered by general practice. Multi-level modelling is proposed to account for clustering effects by practice and a two-stage least squares regression approach to account for expected contamination at the analysis stage. The research is set in Stoke-on-Trent, a mid-sized urban city in central England with a generally poor health profile. Patients included will be those aged between 35 and 74 years who have been identified as being at increased risk of developing cardiovascular disease. Approximately 920 patients will be recruited in each arm of the trial (20 control, 20 treatment in each of 46 practices). Usual primary prevention care (control) will be compared with usual primary prevention care plus bespoke lifestyle support (treatment). The primary outcome measure is the Framingham 10-year cardiovascular disease risk at one year. Intermediate outcomes: weight, physical activity and health-related quality of life, will be determined at six months to monitor progress with treatment. Change in individual risk factors: blood pressure, lipid profile, weight, body mass index, waist circumference, smoking, diabetes and cardiovascular disease status and medications will also be measured at one year to help understand the specific mechanisms by which the primary endpoint was achieved.