Buffalo Grove, officially the Village of Buffalo Grove, is a village in Lake and Cook County, Illinois. A suburb of Chicago, it lies about 30 miles (50 km) northwest of Downtown Chicago. It totals 9.6 square miles (25 km2) of land, with the top three-quarters in Lake County and the bottom quarter in Cook County. Roads in the village such as Lake Cook Road and Illinois Route 83 converge on I-294, which take drivers to O'hare International Airport 20 miles (32 km) south of Buffalo Grove. As of the 2020 Census, Buffalo Grove has a population of 43,212.
Before westward expansion, Native American Potawatomi tribes inhabited the present area. The name "Buffalo Grove" comes from the English translation of the Potawatomi name for Buffalo Creek, which flows through some of the village. Initial Homesteaders sold their land to agricultural Catholic German immigrants, who established St. Mary's Church and a school. The rural area changed minimally until post-Korean War developers bought and suburbanized the region for veterans. After being incorporated in 1958, Buffalo Grove experienced a population boom for the next three decades and hosted a 50th Anniversary Celebration in 2008.
Nearly all schools in Buffalo Grove have achieved commendable status or received awards from the state in the 21st century. The village features dozens of recreational facilities, parks, and festivals, including a months-long Farmers' market, two golf courses, and popular Buffalo Grove Days. Although its schools and low crime are attractive to moving families, the village's population has plateaued since 2000. Buffalo Grove has an elected council-manager government with home rule status. Because of Buffalo Grove's location in two counties, different state and national districts represent each portion. The local government's public works department is nationally accredited. Economically, residents work in health care, education, and professional services, while businesses in the village employ 20,000 daytime workers in 10 million square feet of commercial and industrial space.