Web services technologies promise to create new business applications by composing existing services and to publish these applications as services for further composition. The business logic of applications is described by abstract processes consisting of tasks which specify the required functionality. Web services provision refers to assigning concrete Web services to perform the constituent tasks of abstract processes. It describes a promising scenario where Web services are dynamically chosen and invoked according to their up-to-date functional and non-functional capabilities. It introduces many challenging problems and has therefore received much attention. In this article, the authors provide a comprehensive overview of current research efforts. The authors divide the lifecycle of Web services provision into three steps: service discovery, service selection, and service contracting. They also distinguish three types of Web services provision according to the functional relationship between services and tasks: independent provision, cooperative provision and multiple provision. Following this taxonomy, we investigate existing works in Web services provision, discuss open problems, and shed some light on potential research directions.