An emergency services district is a political subdivision of the State of Texas, just like a school district. An emergency services district can provide fire protection, emergency medical services, or both.
Emergency services districts can overlap. Comal County ESD #1 overlaps Comal County ESD #4 (fire protection through Spring Branch Fire Department) and Comal County ESD #5 (which provides fire protection through Bulverde Fire Department). Comal County ESD #1 trains firefighters from these other districts for medical first-response, but the districts do not share revenues. Each is a distinct governmental unit.