Well–being, health and freedom are some of the many phenomena of interest to science whose definitions rely on a normative standard. Empirical generalizations about them thus present a special case of value-ladenness. I propose the notion of a ‘mixed claim’ to denote such generalizations. Against the prevailing wisdom, I argue that we should not seek to eliminate them from science. Rather, we need to develop principles for their legitimate use. Philosophers of science have already reconciled values with objectivity in several (...) ways, but none of the existing proposals are suitable for mixed claims. Using the example of the science of well-being, I articulate a conception of objectivity for this science and for mixed claims in general. _1_ Introduction _2_ What Are Mixed Claims? _3_ Mixed Claims Are Different _3.1_ Values as reasons to pursue science _3.2_ Values as agenda-setters _3.3_ Values as ethical constraints on research protocols _3.4_ Values as arbiters between underdetermined theories _3.5_ Values as determinants of standards of confirmation _3.6_ Values as sources of wishful thinking and fraud _4_ Mixed Claims Should Stay _4.1_ Against Nagel _5_ The Dangers of Mixed Claims _6_ The Existing Accounts of Objectivity _6.1_ The perils of impartiality _7_ Objectivity for Mixed Claims _8_ Three Rules _8.1_ Unearth the value presuppositions in methods and measures _8.2_ Check if value presuppositions are invariant to disagreements _8.3_ Consult the relevant parties _9_ Conclusion. (shrink)