Climate change is one of the greatest challenges encountered by modern states and humanity on the whole. It has a huge impact on almost all foreign policy challenges in the 21st century. Scientists and experts have reached agreement about its significance. However, there is no political consent and formulation of an efficient political response. Since climate change occurs globally, the political response to it must be international, regional and local. In order to respond efficiently to climate change, it needs to be properly understood and adequately analyzed, and states must have the capacity to successfully deal with that challenge in their respective foreign policies. In other words, states must build internal capacities for successful conduct of climate diplomacy that, since the emergence of this challenge on the international agenda, at the beginning of the 1990sm has become the main foreign policy instrument in the development of the international climate regime. From the first global UN Summit in Rio (1992) to the most recent one in Glasgow (2021), the climate regime was developed more or less rapidly, depending on the major or minor successes of climate diplomacy. Nowadays, with the consequences of climate change being more evident and with citizens raising their voice, states cannot allow themselves to be amateurs in that area of foreign policy activity. The modified concept of international relations that has also brought along the modified concept of security has a broader view than the exclusive orientation to the state. All this also includes the countries of Southeast Europe which are able to make an actual contribution through successful climate diplomacy, as well as improve mutual regional cooperation and strengthen their economic development.