Abstract-This paper presents a new policy language, known as functionality-based application confinement policy language (FBAC-PL). FBAC-PL takes a unique approach to expressing application-oriented access control policies. Policies for restricting applications are defined in terms of the features applications provide, by means of parameterised and hierarchical policy abstractions known as functionalities. Policies also include metadata for management and the automation of policy specification. The result is a novel scheme for application confinement policy that reuses, encapsulates and abstracts policy details, and facilitates a priori policy specification: that is, without having to rely solely on learning modes for creating policies to restrict applications. This paper presents the policy language, and illustrates its use with examples. A Linux-based implementation, which uses FBAC-PL, has demonstrated that this approach can overcome policy complexity and usability issues of previous schemes.