Europe’s pursuit of greater defence readiness is reshaping not only its security policies, but also the geography of its industrial partnerships. This policy brief examines the strategic role of the Western Balkans as a defence-industrial contributor to Europe’s evolving security architecture. It argues that the region’s manufacturing capacity, cost advantages, and proximity can help address Europe’s current production constraints while reinforcing long-term strategic autonomy. By linking defence cooperation to the enlargement process, the analysis reframes integration as a mutually beneficial, capability-driven partnership that strengthens Europe’s resilience and gives concrete meaning to the Western Balkans’ European future.