EMPOWER is a multidisciplinary research and innovation effort aiming to developing, implementing, evaluating and disseminating the effectiveness and cost-effectiveness of a modular eHealth intervention platform to promote health and well-being, reduce psychological distress, prevent common mental health problems and reduce their impact in the workplace. In collaboration with stakeholders, we will adapt existing effective interventions focused on different components (awareness and stigma, workplace conditions and psychosocial factors, stress, common mental health symptoms, early detection, comorbidity, lifestyle, and return to work) to created a combined online modular platform feasible in various workplace settings by culturally and contextually adapting it. The intervention will be implemented through a randomized controlled trial directed to employees and employers of small and medium sized enterprises and public agencies from three European countries (Spain, Finland and Poland). Both qualitative and quantitative methods will be used in the evaluation of the individual health outcomes, cost-effectiveness (from a social, economical, employer and employees perspective), and implementation facilitators and barriers. Implementation strategies relevant to the uptake of the EMPOWER intervention will be identified, including a realistic appraisal of barriers to uptake as well as evidence-based solutions to these barriers. Through scaling-up pre-existing effective and cost-effective interventions, EMPOWER is aimed at addressing the overarching challenges from different perspectives, including individual level (e.g., addressing stigma, mental health, well-being and lifestyles, taking into account legal, cultural and gender issues) and organizational level. The main outcomes effort will help employees, employers and policymakers in decision processes of new legal and contractual framework at EU and national level covering the new economy landscape.