While most public health practice is done by state and local agencies, the federal government provides most of the financial support and much of the expertise that defines the state programs. In some areas, such as environmental and occupational health, the federal government has a primary regulatory role. The federal government operates many health care facilities and provides other services that affect the public health.

The federal government provides many services through private contractors. There is an extensive body of federal law on the rights and duties of contractors, which includes health and public health practitioner and facilities which participate in federal programs such as Medicare and Medicaid. Contract disputes are generally handled by the court of claims system.

The federal government is immune from damage claims for its actions unless it waives that immunity through the Federal Tort Claims Act or other legislation. These laws waiving immunity provide the only mechanism for suing the federal government for tort damages, and, as discussed later, some types of damages, such as defamation, cannot be recovered against the federal government.