In recent years, the inefficiency and sluggishness of traditional multilateral institutions in Eurasia have prompted states to seek alternative, more flexible arrangements. This study analyzes agreements based on minilateralism in Eurasia and focuses on why states, alongside multilateral institutions such as the Shanghai Cooperation Organization and the Eurasian Economic Union, turn to smaller, more flexible pacts. The main research question asks why these agreements form, and the hypothesis states that they emerge primarily as complementary mechanisms to multilateral institutions, in response to the limitations and sluggishness of traditional institutions, as states seek a faster, more targeted, and less costly mechanism to address regional threats and opportunities. Adopting a descriptive-analytical approach through document review and case studies, the research examines the structural, security-geopolitical, and economic factors shaping these agreements and their differences from traditional multilateral institutions. The findings indicate that these agreements operate primarily as complementary mechanisms alongside traditional multilateral institutions and, under conditions of institutional gridlock, provide capacity for more effective and flexible coordination among member states. Finally, the article highlights the importance of these arrangements in redefining patterns of regional cooperation and in understanding future power dynamics in Eurasia.