This session describes the current thinking about emergent design, discovering design in code. The hazard of Big Design Up Front in software is that you don't yet know what you don't know, and design decisions made too early are just speculations without facts. Emergent design techniques allow you to wait until the last responsible moment to make design decisions. This talk covers four areas: emergent design enablers, battling things that make emergent design hard, finding idiomatic patterns, and how to leverage the patterns you find. It includes both proactive (test-driven development) and reactive (refactoring, metrics, visualizations, tests) approaches to discovering design, and discusses the use of custom attributes, DSLs, and other techniques for utilizing them. The goal of this talk is to provide nomenclature, strategies, and techniques for allowing design to emerge from projects as they proceed, keeping your code in sync with the problem domain.