David Henderson was both a scholar and a practising economic adviser. He was always concerned with what was going on in policy analysis and in the technical economics, or other thinking, which lay behind economic policy. He was widely and deeply read, not only in economics: he published many books, was a prolific contributor to policy journals and gave many lectures, including the Reith Lectures of 1985. He was an active networker, always reaching out to those who could help him or those he wished to influence. I have first written about the man I knew and second about the contribution to policy advice contained in his writings.