Efforts to induce energy-friendly behavior from end users through behavioral interventions are characterized by lack of customer personalization (“one-size-fits-all interventions”), partial understanding about how different interventions interact with each other and contrasting evidence about their effectiveness, as a result of poor testing under real world conditions. The NUDGE project has been conceived to unleash the potential of behavioral interventions for long-lasting energy efficiency behavior changes, paving the way to the generalized use of such interventions as a worthy addition to the policy-making toolbox. We take a mixed approach to the consumer analysis and intervention design tasks combining surveys and field trials. Firmly rooted in behavioral science methods, we study individual psychological and contextual variables underlying consumers’ behavior to tailor the design of behavioral interventions for them, with a clear bias towards interventions of the nudging type. The designed interventions are compared against traditional ones in field trials (pilots) in five different EU states, exhibiting striking diversity in terms of innovative energy usage scenarios (e.g., PV production for EV charging, DR for natural gas), demographic and socio-economic variables of the involved populations, mediation platforms for operationalizing the intervention (smart mobile apps, dashboards, web portals, educational material and intergenerational learning practices). We are a multidisciplinary team of 10 partners marking solid expertise in behavioral science, (mobile) user interface and policy design; synergies of different stakeholders (energy providers/cooperative/communities, consumer associations, technology providers); and extensive networks of expert groups, industrial & consumer associations amplifying our potential for tangible impact on policy-making at all levels.