The Multi-Materials Stewardship Board (MMSB) is a Crown agency of the Government of Newfoundland and Labrador, reporting to the Minister of Environment and Conservation. It was established in 1996 to develop, implement and manage waste diversion and recycling programs on a province-wide basis for specific waste streams designated by the government.

Since 1996, MMSB has worked with various stakeholders throughout Newfoundland and Labrador to develop and implement recycling and waste diversion programs to ensure a clean and healthy environment throughout the province. These initiatives include the Used Beverage Container Recycling Program, Used Tire Management Program, Used Oil Recycling Program, Residential Backyard Composting Program and Public Education Programs.

MMSB is a self-financed Crown agency that does not receive any funding from the Government of Newfoundland and Labrador. Its revenues are derived from levies applied on various waste streams as authorized and prescribed under provincial legislation (presently beverage containers and tires), as well as from the sale of recyclable materials it collects under its various programs.