Infinite Counsel: A Lawyer's Guide to Understanding Artificial Intelligence and the New Economics of Practice helps lawyers, firm leaders, and legal professionals make sense of generative AI and the economic disruption it brings to law. Trial attorney and legal futurist Jonathan T. Nessler explains AI in plain language, then connects it to the realities of practice: why the billable hour became dominant, how alternative fee arrangements shift incentives, how staffing and leverage drive profitability, and how client demands and access-to-justice pressures are accelerating change. He then demystifies large language models, including how they generate answers, where they can fail, how context and "memory" limits affect outputs, and how to craft better prompts for legal research, drafting, analysis, and revision (with examples of weak versus strong instructions). The book surveys real-world uses of frontier models and specialized legal-AI tools for discovery, document review, writing, and workflow automation, while addressing confidentiality and data-security considerations for responsible adoption. Finally, it looks ahead to AI agents and the "infinite counsel" horizon - competent legal advice replicated at scale - and what it means for pricing, competition, regulation, and the evolving role of the lawyer in an era moving toward AGI and ASI.