Graham Nuthall was drawn to social constructivist theories but relatively pessimistic about the feasibility of social constructivist approaches to teaching, except in rather narrowly specified situations. This article summarizes Nuthall's views on these issues and the research findings that shaped them, drawing in particular on a chapter in which he spoke to the issues directly. The author then draws on some of his work to support and elaborate on Nuthall's conclusions, and argue for more theory and research on both the affordances and constraints of social constructivist teaching.