The concept of well-being is increasingly gaining acceptance as an object of science, and many different types of well-being measures have been developed. A debate has emerged about which measures are able to capture well-being successfully. An important underlying problem is that there is no unified conceptual framework about the nature of well-being—a hotly debated topic of philosophical discussion. I argue that while there is little agreement about the nature of well-being in philosophy, there is an important agreement on some (...) important principles relevant for its measurement. I argue that well-being science has good reasons to accommodate these principles, but currently fails to do so. (shrink)