Project sustainability is a recent concept predominantly debated and employed by international aid organisations working within the field of development aid. It is deemed to be a high-level examination whether the aid intervention has been successful or not. Even though all the international aid organisations examined in the thesis share the viewpoint that project sustainability has to do with the maintenance of the achieved outcomes after the aid intervention has come to an end, there are some shortages in their definitions of the term as well as the factors that can affect project sustainability. The thesis is thus concerned with analysing the sustainability of the project Industrial and Urban Development in Viet Tri city (Vi t Trì Project) financed by the Danish International Development Agency (Danida) and implemented in Vi t Trì city, Phú Th province from July 2002 to July 2005. The main aim is to obtain deeper practical knowledge and understanding of project sustainability, the factors that can affect project sustainability in reality, and the improvement possibilities.