Abstract: A Magnetic Retention Device comprising an elongated, pliant strap with a magnet set at each end that magnetically associate with each other. The magnet ends of the Magnetic Retention Device secure a flexible bag inside a waste container by magnetic association through the side of the waste container and side of flexible bag. A plurality of Magnetic Retention Devices can be used to secure two or more sides of the flexible bag to the inside of the waste container. The Magnetic Retention Device can serve as a handle to a single side of a flexible bag in order to hang the bag from a rigid arm.