High quality public services constitute the backbone of citizens’ social welfare and are also essential to a region’s competitiveness and business entrepreneurship. Delivery of high quality public services is instrumental so that society and its economy can function. Despite this, the future provision of public services faces significant social challenges, as stated in H2020 “Understanding Europe - Promoting The European Public And Cultural Space”. Key challenges include those due to demographic change and others, related to the EU´s continued search for a model of advanced economic and social development compatible with demands for competition in a globalized economy. All of these longer-term challenges mean that public service provision must be reinforced on the basis of more and better innovation, and greater efficiency and productivity. CITADEL will create an ecosystem of best practices, tools and recommendations to transform Public Administrations (PAs) via an inclusive approach in order to provide stakeholders with more efficient, inclusive and citizen-centric services. The CITADEL ecosystem will allow PAs to use what they already know and new data to implement what really matters to citizens in order to shape and co-create more efficient and inclusive public services. CITADEL innovates by using ICTs to find out why citizens stop using public services, and use this information to readjust provision to bring them back in. Also, it identifies why citizens are not using a given public service (due to affordability, accessibility, lack of knowledge, embarrassment, lack of interest, etc.) and, where appropriate, use this information to make public services more attractive, so they start using the services. CITADEL will be implemented and validated in four use cases in Latvia, Italy, The Netherlands and Belgium.