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Agricultural sustainability is enhanced by management practices that optimize the performance of multiple agroecosystem functions. The performance of western Corn Belt cropping systems was evaluated based on four agroecosystem functions: food production, raw materials production, nutrient cycling, and greenhouse gas regulation. A simple multiattribute ranking procedure was used to quantify agroecosystem performance using data from a long-term cropping systems experiment near Mead, NE. Treatments included in the procedure were continuous corn (Zea mays L.) (CC), corn–soybean [Glycine max (L.) Merr.] (C–SB), corn–oat (Avena sativa L.) _ clover [80% sweet clover (Melilotus officinalis L.) and 20% red clover (Trifolium pratense L.)]–sorghum [Sorghum bicolor (L.) Moench]–soybean (C–OCL–SG–SB), and corn–soybean–sorghum–oat + clover (C–SB– SG–OCL) each at three N fertilization levels (ZERO, LOW, and HIGH). Based on treatment averages of soil and crop indicators from 1983 to 1998, agroecosystem performance scores ranged from 66.6 to 77.3, with a least significant difference (LSD) between treatments of 2.2 (P < 0.05). Treatments with the highest scores included C–OCL– SG–SB/LOW (77.3), C–SB/LOW (76.9), CC/LOW (76.7), CC/HIGH (76.6), and C–SB–SG–OCL/LOW (75.3). Among these treatments, those fertilized at the LOW N rate attained high scores through moderate performance in all four agroecosystem functions. The CC/ HIGH treatment, however, attained a high score solely through its superior capacity to be highly productive, as its scores for the two environmental quality–related functions were the lowest among all treatments. Correlations between production- and environmental protection–related functions were negative, emphasizing the importance of employing management practices that are productive yet minimize deleterious environmental impacts.