Midland is a city in the U.S. state of Michigan in the Flint/Tri-Cities region of the state. It is the county seat of Midland County. While the vast majority of the city exist within Midland County, a small portion of the city extends into Bay County. Most of the city's area is incorporated from Midland Township. The city's population was 41,685 as of the 2000 census. The 2008 census estimate places the population at 40,917. It is the principal city of the Midland Micropolitan Statistical Area. The portion of the city in Bay County is included in the Bay City Metropolitan Statistical Area for statistical reasons. The Dow Chemical Company was founded in Midland in 1897. Its world headquarters are still located there. Through the influence of a Dow Chemical plant opening in Handa, Aichi, Japan, Midland and Handa have become sister cities. The Dow Corning Corporation and Chemical Bank are also headquartered in Midland.