Four years ago, I reviewed Business and Commercial Litigation in Federal Courts (3d ed.), concluding then that notwithstanding the dwindling “brick-and-mortar,” traditional law libraries, this multi-volume treatise is a worthy tool in the arsenal of the business litigator. Well, now nineteen years after its inception, the treatise, Business and Commercial Litigation in Federal Courts (4th ed.) (“BCL”), is in its Fourth Edition, having added twenty-five new chapters leading to three more volumes. Is it still worth the shelf space? Unquestionably, this landmark treatise remains an essential guide for commercial litigators and in-house counsel alike. The addition of the new chapters is an important recognition of the evolution of commercial litigation that plays out in the federal courts. As with the past editions, the roster of authors for each of the chapters continues to be a “who’s who” of practitioners and judges well-known in the commercial arena.