Soil quality assessment is based on the concept of soil functions. The performances of three soil functions, crop production, biological decomposition and matter exchange with the atmosphere and groundwater, are used as quality criteria. Soil properties that can be used as indicators for the degreeof functional performance were identified. Each soil property selected was graded into five classes - from best (class 1) toworst (class 5). Grading was based biological on boundary conditions as well as on statistical distribution. The system outlined can be used to interpret the quality state of agricultural soils, provides for a relative comparison between soils, and may be helpful in an environmental monitoring program to assess trends in data.