Abstract: The invention is concerned with a collapsible support for bags which is formed from a one-piece blank made of flexible sheet material and has fastening means holding the sheet material to define an open-ended form-retaining structure for receiving a bag and supporting same in an upright open-mouthed position. The form-retaining structure has a solid circumferential sidewall extending substantially the full height of the bag in its upright position, whereby to permit a peripheral end portion of the bag to be retained folded over an upper edge of the sidewall. The bag support of the invention permits the bag to be easily withdrawn therefrom, prevents sharp objects from piercing the bag when it is inserted into the bag to form a protective liner for the bag, and can be collapsed for convenient storage and/or handling.