Greater Harris County 9-1-1 Emergency Network (GHC 9-1-1) was established in November, 1983. The mission of Greater Harris County 9-1-1 Emergency Network (GHC 9-1-1) is to implement and administer 9-1-1 emergency service—emergency call delivery—for all cities wholly or partially within Harris County and for the unincorporated area of the County. With the enactment of SB621, by the 79th Legislature, the GHC 9-1-1 territory was expanded to include all of Fort Bend County.

In total, GHC 9-1-1 administers service for 49 cities, 2 counties and in excess of 150 police, fire, and emergency medical agencies. There are nearly 50 fully equipped 9-1-1 answering points within the GHC 9-1-1 service area.

The 9-1-1 service established by GHC 9-1-1 in January, 1986 was the first fully enhanced service in the State of Texas. It is the largest 9-1-1 system in Texas and the third largest regional 9-1-1 system in the nation.

Over 9,000 calls per day are made to 9-1-1 in the area served by GHC 9-1-1. Up to 73% of those calls are from wireless phones.