Lipid analysis should be tailored to the likelihood of hyperlipidemia and atherosclerosis. In healthy individuals without a family history of hyperlipidemia, it is sufficient to obtain readings of total cholesterol and high-density lipoprotein (HDL) cholesterol. In patients with a family history of hyperlipidemia, in addition, triglycerides should be measured. In patients with manifest atherosclerotic disease, the lipid profile should always include plasma cholesterol and triglycerides as well as HDL cholesterol; if these do not explain presence or extent of atherosclerosis, apolipoprotein (a) should be measured. Patients with diabetes mellitus should undergo the same diagnostic work-up as those with atherosclerotic disease. An apolipoprotein B reading (together with triglyceride levels) is sometimes helpful in patients with diabetes mellitus, allowing to estimate the size of triglyceride-rich lipoproteins. In patients with pancreatitis, longitudinal assessment of plasma triglycerides and, if available, measurement of HDL triglyceride are useful to unmask underlying hyperlipidemia.