The Mannheim Carotid Intima-Media Thickness Consensus (2004–2006) addresses the standardization of carotid intima-media thickness (IMT) measurements and the classification of early atherosclerotic lesions. The consensus emphasizes the importance of distinguishing between early atherosclerotic plaque formation and IMT thickening, defining plaque as a focal structure encroaching into the arterial lumen or demonstrating a thickness >1.5 mm. Standardized methods for IMT measurement are recommended to ensure homogenous data collection and analysis, which is crucial for improving the power of randomized clinical trials and facilitating meta-analyses. The consensus also provides guidelines for ultrasound acquisition and analysis, including optimal equipment settings, scanning protocols, and quality control measures. While IMT has been suggested as an important risk marker, it does not meet the criteria of an accepted risk factor. The consensus concludes that there is no need to 'treat' or monitor IMT values in individual patients, except in specific contexts within randomized clinical trials.The Mannheim Carotid Intima-Media Thickness Consensus (2004–2006) addresses the standardization of carotid intima-media thickness (IMT) measurements and the classification of early atherosclerotic lesions. The consensus emphasizes the importance of distinguishing between early atherosclerotic plaque formation and IMT thickening, defining plaque as a focal structure encroaching into the arterial lumen or demonstrating a thickness >1.5 mm. Standardized methods for IMT measurement are recommended to ensure homogenous data collection and analysis, which is crucial for improving the power of randomized clinical trials and facilitating meta-analyses. The consensus also provides guidelines for ultrasound acquisition and analysis, including optimal equipment settings, scanning protocols, and quality control measures. While IMT has been suggested as an important risk marker, it does not meet the criteria of an accepted risk factor. The consensus concludes that there is no need to 'treat' or monitor IMT values in individual patients, except in specific contexts within randomized clinical trials.