The need to develop appropriate ways to measure sustainability of agricultural systems is today a very important aspect for researchers, politicians, farmers and society.

Agroecosystem Performance Indicators (APIs) should be a means that allow us to develop and understand the sustainability of agricultural processes at crop, farm and regional level, to facilitate decision-making processes.

APIs are elaborated and based on an input/output methodology of analysis in terms of both energy and monetary values. These measurements are sufficiently homogenizing and comprehensive to document patterns of agroecosystem transfers of biophysical entities and socio-cultural values.