Most of the theoretically based QOL indicators projects can be classified in terms of six major theoretical concepts: (a) socio-economic development (b) personal utility, (c) just society, (d) human development, (e) sustainability, and (f) functioning. I explain the core aspects of these six theoretical paradigms and show how they help guide QOL researchers to select and develop QOL indicators that are significantly and qualitatively distinct. A taxonomy of QOL indicators guided by a given theoretical concept is likely to be very different from others taxonomies guided by different theoretical concepts. Thus, the objective of this paper to explain these theoretical paradigms and show how they guide QOL researchers to select and develop QOL indicators that are significantly and qualitatively distinct.