Waste Management, Inc. is a holding company, which engages in the provision of waste management environmental services. It operates through the following segments: Collection and Disposal-East Tier (East Tier), Collection and Disposal-West Tier (West Tier), Recycling Processing and Sales, WM Renewable Energy, and Corporate and Other. The East Tier segment includes the Eastern United States, the Great Lakes Region, and Canada. The West Tier segment refers to the upper Midwest region and British Columbia, Canada. The Recycling Processing and Sales segment focuses on the processing and sales of materials collected from residential, commercial, and industrial customers. The WM Renewable Energy segment develops, operates, and promotes projects for landfill gas use. The Corporate and Other segment relates to its corporate office activities. The company was founded on September 30, 1987 and is headquartered in Houston, TX.