The quality of children's life is important both as an investment in the future of our society and because children constitute an important group of themselves and deserve to experience well-being presently. Quality of life (QOL) has been conceptualized and studied in children for several decades, but with disparate approaches that have rarely been discussed jointly with application to children in general. Here we describe and critically examine the three main approaches to children's QOL: health-related QOL (HRQOL), social indicators, and subjective well-being (SWB). Although this is not a review of instruments per se, we illustrate these approaches by describing their most prominent measures. Issues and opportunities in research on children's QOL are then discussed related to conceptual clarity, content specification, range of experience, subjective and objective perspectives, development in childhood, reporting source, and malleability of QOL. Finally, directions for advancing children's QOL are considered. We highlight the benefits of focusing on social indicators and SWB, rather than HRQOL, when representing this concept for children in general, the need for applying more sophisticated research strategies, and using QOL as a universal indicator of success whenever we intend to advance the well-being of children through intervention, programs, and policy.