This article draws out the ways in which Justice Rothstein grappled with complexity in administrative law. It argues that Justice Rothstein took a pragmatic approach to complexity in administrative law. Specifically, he sought to articulate a framework for judicial review that was workable for administrative decision-makers, litigants, their lawyers and reviewing courts. In addition, he looked to past experience with judicial review, evidenced in judicial precedent, rather than focusing on abstract theoretical norms.