KPI stands for “Key-Performance-Indicators” and is frequently used for parameterisation and quantification of quality standards, i.e. in “Quality Assessment” studies. “Quality Assessment & KPI” are important aspects in the evaluation of sustainability in production and services. The theoretical concepts and aspects of “Sustainability” provide solid underlying structure for using “Quality Assessment & KPI” to evaluation the performance of “Applied Sustainability” and thereby make “sustain-earth” a coherent and integrated body what regards achieving socio-economic developments in all sectors and on different levels.