This project aims at improving ambient air quality in the Municipality of Vidin by reducing PM10 emissions from domestic heating as one of the main sources of air pollution. The specific objectives are: analysis and definition of concrete solutions for PM10 reduction; replacement of household solid fuel appliances with alternative types of heating appliances. The project will be implemented in two stages. In the first phase, all actions to prepare the investments will be carried out. An explanatory/training campaign will be organised and conducted among the population on possible alternative forms of heating and the conditions for inclusion of the population in the replacement scheme. A survey of the attitudes among the residents of the municipality, who are heated with solid fuel, will be carried out to replace the heating appliances they use. Environmental, economic and social analyses will be prepared, criteria and mechanisms for prioritisation of districts/areas in the municipality’s settlements will be developed for applying different heating options and contributing to the reduction of PM10 emissions. Sites/households will be surveyed for the actual technical parameters for replacement with alternative heat sources. The first stage will end with the preparation of a comprehensive vision for the approach of the Municipality of Vidin to replace solid fuel heating devices. During the second investment stage, based on the results of the first stage, Vidin Municipality will select contractors according to the Public Procurement Act and will implement the investment activities for dismantling the used heating devices and for supply and installation of the new heating appliances/systems according to the technical solutions of stage I. The environmental benefits will be saved PM10 emissions and improved ambient air quality. The socio-economic benefits will be improved health and quality of life of the population of Vidin Municipality and increased public awareness of the need to improve air quality.