Abstract: Ozone laundry systems and related methods are shown and described. In one embodiment, an ozone laundry system includes a washing machine; an ozone generator, a Venturi-injector, a secondary injection device, and an ozone control system (OCS). The washing machine may have a vented drum for holding laundry and a liquid wash bath, and include a plurality of operational configurations. The OCS may be configured to provide ozone to the Venturi-injector when the washing machine is in the fill configuration, and provide ozone to the secondary injection device when the washing machine is in the wash configuration. The result is a system that is able to maintain ozone at a high level for a duration.