In this chapter, I’m going to try to give you a quick overview of recent developments in biomarkers, but particularly with reference to what we’ve been doing on the Health and Retirement Study (HRS). I anoint the beginning of this movement with the publication of this volume Cells and Surveys from a National Academy panel that endorsed the use of biomarkers in population surveys aimed at social science analysis. And one way to think about it is, it’s kind of a migration from studies which were mostly clinic based, even convenience samples, but some of which were working toward getting locally quasi-representative population samples, and then seeing what of the work being done there could be translated to surveys that had much more direct intent for population representation. There’s now been a companion volume in 2007 that reports on the uptake of these biomarker ideas in a number of studies, including a paper by me on how we did it in HRS.