Abstract: A high performance squeeze bottle dispenser includes an internal product-containing bag which is in fluid communication with a dispensing nozzle. The dispensing nozzle is airtight to prevent air from escaping back into the bag when pressurization of the bottle is released. A one-way air valve in a wall of the bottle admits air into the interior of the bottle around the outside of the product bag to provide a pumping action which pressurizes the interior of the bottle to cause product expulsion through the nozzle. An inversion collar projects into the bag so that the bag folds inwardly upon itself and up into the collar as product is expelled. The collar may also include an upper inside dome-shaped surface which matches the shape of the inside of the bottom of the bag to achieve near-complete expulsion of product to reduce waste.