Waste Management, Inc. is a holding company, which engages in the provision of waste management environmental services. It operates through the following segments: East Tier, West Tier, and Other. The East Tier segment consists of Eastern U.S., the Great Lakes Region, and Canada. The West Tier segment includes the upper Midwest region and British Columbia, Canada. The Other segment covers segments which are not evaluated and overseen through the East and West Tiers. The company was founded on September 30, 1987 and is headquartered in Houston, TX.