Microalbuminuria is an important predictor of the development of clinical nephropathy in diabetic patients. In this study we have evaluated the sensitivity and specificity of a rapid semi-quantitative method for the detection of microalbuminuria (Microbumintest tablets) in comparison with radio-immuno-assay. When the cut-off point for albumin concentration was set at ≥40 mg/l the sensitivity and specificity were 97.2% and 92.2%, respectively. Although the tablets are relatively expensive for screening purposes, we conclude that they represent a reliable and convenient screening method for microalbuminuria in diabetic patients.