Updated project metadata. Cardiovascular diseases represent a leading cause of deaths globally; of which atherosclerosis is a major contributor. Selective retention of circulating apolipoprotein B particles in the sub endothelial space by arterial wall proteoglycans and their subsequent modification is currently thought to be a hallmark of the disease. The exact mechanism responsible for lesion development is not fully understood. Currently, ultrasonic assessment of carotid artery intima media thickness (IMT) is commonly used as a pre-clinical marker of atherosclerosis. However, as the onset of atherosclerotic process and the appearance of carotid artery plaque can vary, the identification of additional biomarkers showing potential etiological aspects of disease is an important goal. This study describes the use of a label free mass spectrometry approach in the proteomics analysis of serum samples from control and atherosclerotic subjects. The samples were from a study cohort recruited in The Cardiovascular Risk in Young Finns Study, with a goal of identifying biomarkers for atherosclerosis. Samples from 43 individuals with a early non-obstructive plaques and 43 controls were used (Matched by age, sex, body size and systolic blood pressure).