This essay responds to the pieces in a special forum in History Australia on historians’ public and political responsibilities in “urgent times.” It does so by discussing historian as “time workers,” and by exploring the concept of history’s “externalities”: What have historical actors identified as outside their spheres of analysis and concern, and what do they place on the inside? Similarly, what do historians place outside and inside the boundaries of their scholarship? The essay argues for the benefits of mapping these inside/outside relationships and, in each instance, for the ethical importance and analytical advantages of bringing the externalities “in.”