Measurement of traditional risk factors remains the foundation of current clinical practice guidelines when screening for coronary heart disease (CHD) risk. However, many adults who experience CHD events are not identified as higher risk based on their traditional risk factors. Observational data show that the coronary artery calcium (CAC) score improves risk prediction, even after taking into account traditional risk factors. The authors have outlined several principles of CAC testing into a list of dos and don'ts to help maximize its potential benefit while minimizing potential harm.