Sustainable Development Goals guide both developed and developing countries to achieve a sustainable future. In particular, the 2030 Sustainable Development Goals clearly state what needs to be done or achieved by 2030 with 17 specific basic and sub-goals. In this respect, it can be considered a concrete guide for the 2030 SDGs. On the other hand, the 2030 SDGs or sustainable development can't progress together with the current economic system. At this point, the green transition has come into play. The green transition and circular economy system can make countries’ sustainable transformations realistic. Adapting to green transition and circular economy practices is not equally easy for every country. The transition to and adaptation to circular economy practices may vary depending on the country's structure, population, economic power, size, and many other variables. This study explores the challenges that prevent adaptation to the green transition and circular economy in the long term. As it is purposed, this study will review current statistics, reports, and sources to conclude the main challenges and barriers in transitioning to circular practices.