Federal grant money arrives with an administrative system attached, and organizations that treat the award as revenue rather than as a compliance obligation get into trouble in predictable ways. This article explains how federal assistance actually works: the statutory distinction between a grant, a cooperative agreement, and a procurement contract, and why the label determines everything that follows. It covers the Uniform Guidance and its four operative parts, the cost principles that decide what may be charged, the procurement standards that surprise recipients who thought they could buy however they liked, and the subrecipient monitoring obligations that make a pass-through entity responsible for someone else's compliance. It explains the single audit, what auditors actually test, and what a finding costs. It covers disallowed costs, suspension and debarment, and the False Claims Act exposure that turns a compliance failure into treble damages.