A Diploma Thesis titled “Development of an Optimization Model of Resource Allocation for the Management of Urban Transport Buses” was presented by Ilias Laios in March 2018, aiming to estimate the optimal allocation of the financial resources of the Athens Urban Transport Organization aiming for the most desirable result of the more efficient replacement of bus fleet. A mathematical optimization model based on the principles of linear integer programming was developed and implemented to achieve the goal. The greatest reduction in the cost of bus fleet management results from favorable conditions for the purchase of innovative and more efficient types of buses, such as electric buses and compressed natural gas buses.