The Indiana Supreme Court recently delivered a landmark public trust decision, Gunderson v. State, ruling that the state acquired and still owns Indiana’s bed of Lake Michigan below the ordinary high water mark, including exposed shores, and that it holds that bed in an inalienable trust for public uses. This is a unique decision for the Great Lakes region. This Article examines the legal background for the case, the conflicts and contradictory rulings that emerged as it travelled upward through the court system, and the ultimate resolution by Indiana’s high court. The Article also places the decision in the larger context of environmental conservation and public trust advocacy.