Our atmosphere is becoming more polluted every day. Each morning Kathmandu wakes up to an increasing level of Particulate Matter (PM) and toxic gases. With the population in Kathmandu rising, the situation is more aggravated by the ever increasing number of private vehicles. The air pollution of Kathmandu Valley is considered to be the major threat to human health. In order to address this deteriorating situation, CEN is constantly raising issues of air quality and sustainable urban transport, building capacity of stakeholders, initiating collaborations and creating awareness at local and grassroots level.