We have studied the relationship of serum lipoprotein (a) [Lp(a)], an independent risk factor for cardiovascular disease, with other cardiovascular risk factors and measurements of carotid intima media thickness (IMT) in 241 established Type 2 diabetic subjects, males and females mean age 51 years, with no known cardiovascular disease, screened for entry into a prospective intervention study.The median concentration of Lp(a) in the 27 Afro-Caribbeans (38.5mg/dl) was higher than in the 119 Caucasians (7.9mg/dl) or the 84 Asians (10.0mg/dl) (χ2=15.5 p=0.004). HDL (p=0.0001) HDL2 (p=0.0006), HDL3 (p=02) and LDL cholesterol (p=0.02), and IMT (after normalising) (p=0.02) all had higher means at higher concentrations of Lp(a). Serum triglyceride (p=0.0001), insulin (p=0.0009) and C-peptide (p=0.01) all had lower means at higher Lp(a) concentrations. We have previously shown in this cohort that early ultrasonically measured arterial disease was related to relative fasting hypoinsulinaemia. Lp(a) may be involved in early arterial thickening in Type 2 diabetes through its inverse relationship with serum insulin, but this may not apply to Afro-Caribbeans.