The objective of this thesis has been to explore how leverage by small non-permanent members of the United Nations Security Council (UNSC) can be explained. I have investigated this by examining the efforts by three small non-permanent members, Luxembourg, New Zealand, and Sweden. These states are all known to have achieved leverage in the UNSC in the case of Syria between 2013 and 2018, despite the asymmetrical power structure of the UNSC. The thesis is guided by the theoretical framework of the neoliberal institutionalist perspective and the concept of soft power, to investigate how institutional arrangements of the UNSC, and the states’ identities can help facilitate leverage in the UNSC. I have conducted an explanatory case study and applied congruence method to deductively connect the theories with the empirical evidence. The findings indicate that both theories have explanatory power when used complementary. The conflict in Syria has been a highly politicized and deadlocked case in the UNSC, and leverage by small states should therefore not be exaggerated. However, this thesis illustrates how the UNSC is not only governed by the five permanent members without any impact from small non-permanent members. During their tenures in the UNSC, the three small states in my case study established themselves as leaders of the humanitarian issues regarding Syria in the UNSC and developed several important resolutions. The empirical findings suggest that these states achieved leverage by taking advantage of the existing formal and informal institutional arrangements, especially the procedure of penholdership. The findings further highlight how the identities of the three small states provided the possibility to gain a role as an honest-broker in the humanitarian track. Due to their objective, egalitarian, and legitimate identities they achieved a unique role in the UNSC. This position provided leverage in the specific humanitarian track of Syria, but it also provided a window of opportunity to achieve access into other negotiations. The thesis’ findings are in line with previous studies of small states’ search for influence in international politics and illustrates how small states sometimes can “punch above their weight” within international institutions.