Over the last years, cellular operators, service and content providers, have been trying to identify the needs of a fully connected user, facilitating pervasiveness communications and ubiquitous computing concepts. One of the most promising directions is the so-called context-aware environment. Positioning is an essential component for the deployment of the evolving context-aware concepts. This article introduces a unified positioning component (POS), which establishes a generic, open, modular, and efficient quality of service (QoS) enabled framework, offering independence from the underlying heterogeneous network infrastructures and positioning techniques. The design objectives of POS are presented, as well as its functionality, the technical specifications and the prototype implementation of the POS component, elaborating on the features and services that it offers to the PoLoS platform and middleware location brokering applications.