The present text book of 'Fundamentals of Ecology and Environmental Studies' is written for tertiary institutions. During these past years there has been fundamental change in the attitude of man towards environment. There was a time when environment meant only sanitation and public health. Today, the environment is conceived in its totality, and holistic approach made while planning for better quality of life stressing upon the sustainable development. The human activities have been drastically changing the ecological balance of practically even component the environment viz. atmosphere, hydrosphere, lithosphere and biosphere. There have been efforts on global level for environmental management identifying environmental concerns and planning strategies that suit to particular nation. For instance, in our country the environmental problems where priority action is needed are: Population stabilization, integrated land use planning, Healthy cropland and grassland and conservation of biological diversity, control of air and water pollution, Human settlements, Environmental education and updating environmental law.