International alliances shape foreign policy by fostering collaboration among member states on issues such as security, trade, and development. Alliances like NATO or the EU facilitate joint decision-making, enabling countries to present a united front on global challenges. Such cooperative efforts promote shared interests and collective defense strategies that can deter aggression. Additionally, international alliances can enhance countries' bargaining power in negotiations and contribute to the establishment of international norms and standards. Ultimately, these alliances play a vital role in shaping the geopolitical landscape and influencing bilateral and multilateral relations.