This report discusses the main results of a study on how to reduce air pollution from urban public transport in Kazakhstan. More specifically, it presents the analysis of how to design a green public investment program in this sector.This report discusses the main results of a study on how to reduce air pollution from urban public transport in Kazakhstan. More specifically, it presents the analysis of how to design a green public investment program in this sector. This sector represents an opportunity for Kazakhstan to address key objectives in its environmental and climate-related policies as part of the countrys ambitions to transit to a green economic path of development. In addition to supporting environmental and climate-related objectives, the program is designed to support the modernization of the urban transport fleet in the country as well as stimulate the domestic market to shift to modern buses powered by clean fuels.The program is designed to be implemented in two phases: Phase 1 which covers the cities of Kostanay and Shymkent; and Phase 2 which extends the coverage to all major urban centres in Kazakhstan. Two scenarios for the implementation of the second (extended) phase of the program are developed. Their total cost is estimated to be up to EUR 300 mln. These investments are expected to result in significant air improvement with NOx emissions seeing the greatest decline of up to 2 mln kg/year, whereas CO2 emissions are estimated to decline in an ideal scenario by up to 70 thousand t/year.The OECD is an international organization that consists of 30 Member countries from the developed world that accept the principles of representative democracy and free market economy. It originated in 1948 as the Organization for European Economic Cooperation (OEEC) to help administer the Marshall Plan for the reconstruction of Europe after World War II. Later its membership was extended to non-European states, and in 1961 it was reformed into the OECD. The organizl3#