Stay Sober, Stay Smart was designed around a clear and urgent concern: the high number of road accidents involving young people across Europe, particularly those linked to alcohol and substance use. The project set out not just to raise awareness of this problem but to actively equip young people with the knowledge, tools and confidence to make safer choices on the road and to influence those around them. The starting point was the data. Across the six participating countries, the statistics pointed to a consistent pattern. In Germany, roughly 30% of accidents involving drivers under 30 were linked to impaired driving. Spain reported that 42% of road deaths in 2021 involved drivers who had consumed alcohol or drugs beforehand. Greece saw 38% of all traffic accidents involve young drivers, many under the influence. In Türkiye, up to 35% of fatal accidents had an impairment factor, while Serbia recorded approximately 17% of fatal crashes tied to alcohol consumption. North Macedonia saw around 25% of road accidents involve young drivers with substance use as a contributing cause. These figures made the case for intervention clear and the project took them as its foundation. The first objective was to promote responsibility among young drivers by helping them understand the real consequences of impaired driving; not in abstract terms, but through discussion, simulation and shared experience. Alongside this, the project explored the relationship between mental health, decision-making and substance use, recognising that the choice to drink and drive rarely happens in isolation from broader emotional and social pressures young people face. Peer advocacy was central to the project's approach. Rather than delivering messages top-down, the project aimed to empower participants to become road safety advocates within their own social circles, trusting that peer influence is one of the most effective channels for changing behaviour among young people. This was complemented by real-life simulations, through which participants could practise responding to road scenarios in a safe environment, building the kind of instinctive, practical awareness that formal education often fails to develop. The project also looked beyond individual behaviour toward structural alternatives. Promoting sustainable transport options; public transit, cycling, carpooling was part of the vision both as a road safety measure and as a contribution to broader environmental goals. Media literacy ran through everything: participants analysed how advertising and social media shape attitudes toward alcohol and driving and learned to produce their own counter-narratives using digital tools. Finally, the project aimed to build something lasting. Establishing genuine, working partnerships between the six organisations was not a secondary goal but a core one, with the explicit intention of continuing collaboration under Erasmus+ and sustaining the road safety work beyond the project's own timeline.