This paper introduces the Chemomentum data services, a UNICORE-based flexible solution for managing large amounts of data and metadata produced in a Grid. In order to store and manage the increasing amounts of data produced in Grid environments, a highly scalable and distributed Grid storage system is needed. However, the simple storage of data is not enough. To allow a comfortable browsing and retrieving of the data, it is crucial that files are indexed and augmented with metadata. This paper analyses integrated solutions that already provide these functionalities for their features and shortcomings. Incorporating the conclusions drawn from the examination, an architecture for a revised data management solution is presented. This system provides the means to store files with augmenting extensible metadata. It allows also to browse through data using metadata, handle ontologies and transparently access external data sources. In the current stage, most of these functionalities are implemented and running in a distributed environment.