Subjective well-being (SWB) is an extremely active area of research with about 170,000 articles and books published on the topic in the past 15 years. Methodological and theoretical advances have been notable in this period of time, with the increasing use of longitudinal and experimental designs allowing for a greater understanding of the predictors and outcomes that relate to SWB, along with the process that underlie these associations. In addition, theories about these processes have become more intricate, as findings reveal that many associations with SWB depend on people’s culture and values and the context in which they live. This review provides an overview of many major areas of research, including the measurement of SWB, the demographic and personality-based predictors of SWB, and process-oriented accounts of individual differences in SWB. In addition, because a major new focus in recent years has been the development of national accounts of subjective well-being, we also review attempts to use SWB measures to guide policy decisions.