This examination of the Stock Market’s responsiveness to strikes looks specifically at strike actions that labor historians generally view as the major ones occurring in the United States in the years 1925–37. The authors find that strikes had large, negative effects on industry stock value. Longer strikes, violent strikes, strikes in which unions “won,” industry-wide strikes, strikes that led to union recognition, and strikes that led to large wage increases were associated with larger negative share price reactions than were other strikes. Much of the “news” generated by the typical strike seems to have been registered by the Stock Market very early in the strike. However, there were also some fairly large stock price reactions to news that could be fully revealed only at the end of a strike.