This document discusses the Theory of Constraints (TOC), a management approach that focuses on actively managing constraints that limit an organization's ability to meet goals. It identifies three main types of constraints - bottlenecks, capacity constraints, and demand constraints. A bottleneck is defined as the resource with the lowest capacity in a process. The TOC involves identifying bottlenecks, exploiting them to maximize throughput, and subordinating other decisions to bottleneck management. Key principles include focusing on bottleneck utilization and flow rather than non-bottleneck resources, and pacing work release according to bottleneck capacity.