SaaS refers to a service delivery model where remote software services can be accessed through an interface and combined to create new business services delivered over flexible networks. Hybrid services combine both custom software and product software, such as traffic information from Vodafone. When producing SaaS, software and service producers must consider both product quality and service quality simultaneously. The document then lists examples of SaaS cases from Rabobank, ABNAMRO, and Grexx/SOS International.