Sir: Islamabad, the capital of Pakistan, is the land of green lush grass-covered grounds, tall mountains of the Margalla, wide streets lined with trees, large houses, well-designed public buildings and well-prepared bazaars. Rawalpindi, the twin city of Islamabad, is different. It has narrow streets and old architectural buildings. The two cities though are very close but still, the landscaping, local transport and quality of town planning in each of these cities is different. Like all other big cities, these two cities have a huge population. One of the reasons for the population surge is that the people of small cities often relocate here to earn an attractive income because of reasonably good employment opportunities. This increase of population has no end and this rapid surge in the number of people is now the main cause of environmental problems in these cities. Indeed, the increase in population means the growth of solid waste, increase in wastewater and a substantial increase in noise pollution, etc. On the streets, a number of dirty shopping bags which are floating and flying around cause the birth of flies and mosquitoes. Wastewater is constantly seeping into the natural groundwater, polluting it and increasing the number of waterborne diseases. Like all other developing cities, these twin cities find difficulty in balancing economic development and environmental protection. While competing with the other neighbouring growing cities of the country, Rawalpindi and Islamabad often win as they house small and large-scale factories, production houses, raw material sources and much more. But with the increase in population, the damage and severity of environmental issues increase. Effective measures must be taken to check this damage. Vijdan Saeed Islamabad