The St. Louis County Police Department operates under the authority of the St. Louis County Board of Police Commissioners and is the largest law enforcement agency in St. Louis County.
Although it is directly responsible for law enforcement in unincorporated areas of the county, several municipalities contract with the county police for public safety services.
Municipalities that maintain service agreements with the county police are Black Jack, Clarkson Valley, Dellwood, Fenton, Ferguson, Grantwood Village, Green Park, Hanley Hills, Jennings, Marlborough, Norwood Court, Pasadena Hills, Twin Oaks, Valley Park, Vinita Terrace, Wilbur Park, Wildwood, and Winchester.
A total of 58 of the 90 municipalities in the county maintain their own police departments.
Eighty-one of the local towns run their own courts.

St. Louis County Fire Department services are provided by 20 municipal fire departments and 23 fire protection districts.
The fire protection districts exist as independent, taxing governments that are unrelated to the St. Louis County government, while the municipal fire departments are funded through municipal taxes and are administered by their respective cities.
The St. Louis County Police Department operates under the authority of the St. Louis County Board of Police Commissioners and is the largest law enforcement agency in St. Louis County. Although it is directly responsible for law enforcement in unincorporated areas of the county, several municipalities contract with the county police for public safety services. Municipalities that maintain service agreements with the county police are Black Jack, Clarkson Valley, Dellwood, Fenton, Ferguson, Grantwood Village, Green Park, Hanley Hills, Jennings, Marlborough, Norwood Court, Pasadena Hills, Twin Oaks, Valley Park, Vinita Terrace, Wilbur Park, Wildwood, and Winchester. A total of 58 of the 90 municipalities in the county maintain their own police departments. Eighty-one of the local towns run their own courts.
St. Louis County Fire Department services are provided by 20 municipal fire departments and 23 fire protection districts. The fire protection districts exist as independent, taxing governments that are unrelated to the St. Louis County government, while the municipal fire departments are funded through municipal taxes and are administered by their respective cities.
St. Louis County, Missouri