The Agent Era explores a fundamental question about the future of computing: What happens when software moves from following instructions to pursuing goals? From mainframes and personal computers to the internet and cloud, every major computing shift has changed the fundamental unit of what machines can do. Now, autonomous AI agents may represent the next step in that evolution. This book examines the rise of AI agents, the economics of autonomous software, the future of work and organizations, and the possibility that agents could become a new computing paradigm. It also takes the opposing case seriously, exploring the limits of autonomy, reliability, security, regulation, and the possibility that agents may ultimately become features rather than a fundamental new layer. Thoughtful rather than predictive, The Agent Era is an exploration of where computing may be heading—and what it could mean if software becomes capable of acting on our behalf.