Pay what you want (or PWYW, also referred to as value-for-value model[1][2]) is a pricing strategy where buyers pay their desired amount for a given commodity. This amount can sometimes include zero. A minimum (floor) price may be set, and/or a suggested price may be indicated as guidance for the buyer. The buyer can select an amount higher or lower than the standard price for the commodity.[3][4] Many common PWYW models set the price prior to a purchase (ex ante), but some defer price-setting until after the experience of consumption (ex post) (similar to tipping). PWYW is a buyer-centered form of participative pricing,[5] also referred to as co-pricing (as an aspect of the co-creation of value).