The document reports on the development of interoperability of EN-TRACK with external platforms with a view towards the development of integrated services. It covers the foreseen interoperability with the eQuad and DEEP platforms and the envisaged services are described as use cases, each designed for a specific functionality. Starting from the identified necessities and business context, the use cases are focused from the perspective of development and operation. Each use case description comprises objectives, involved actors, the necessary pre-conditions, and the steps for technical implementation and operation. In relation to eQuad, a platform offering financial and technical assessment of energy efficiency projects and access to investors, EN-TRACK has defined three joint services that could be automated between EN-TRACK and eQuad, adding value to both platforms: • Incorporation of data from eQuad into EN-TRACK • Exporting of benchmarking data from EN-TRACK to eQuad • Enabling access from EN-TRACK for financial assessment of new projects with eQuad In relation to DEEP, an open database for de-risking of energy efficiency investments, two value-added services based on interoperability with EN-TRACK are defined: • Obtaining of benchmarking data from DEEP in EN-TRACK • Uploading of data from EN-TRACK to DEEP The interoperability of data will benefit all platforms through data sharing and reusing of the collected data, setting a core of an ecosystem of complementary tools supporting energy efficiency investments. It will extend the data gathering capabilities of ENTRACK, enable in eQuad access to benchmarking and new customers, and ensure continuous growth of the DEEP database, providing at the same time opportunities for cross-marketing among the platforms. The development of integrated services requires technical implementation and appropriate commercial agreements which will be pursued within the scope of the project. The current document aims to provide a starting point for definition of services of mutual interest. As a public document, it is also useful as an example for definition of joint services with other platforms in the future.