While hundreds of laboratory parameters can be readily analyzed in blood, serum or plasma by standard clinical laboratories, available diagnostic parameters in urine are comparably sparse. Clinical decisions regarding stratification into risk-groups or even treatment of patients frequently need to rely on coarse markers of kidney damage such as the overall protein:creatinine ratio or the albumin:creatinine ratio of urine, supplementing clinical information and the results of kidney biopsy. A quantitative analysis of the protein content of urine appears appealing, as kidney diseases likely leak a protein fingerprint into urine. We will therefore establish state-of-the art technology based on mass spectrometry to compare individual rather than total protein ratios in urine, with the goal of correlating these values to states of health and disease. In the future, such markers may assist clinicians in risk stratification or treatment decisions regarding nephrological patients.