The book is an outcome of the Ph. D. Thesis entitled "Ecology and Economic valuation of Lake Mansar", J&K. The book deliberates in detail on the natural ecosystems that have long been cherished as common property resources, collectively owned by the society at large or owned by no man, with open access to everyone. But due to demotechnic growth the natural senescence process of these ecological systems is accelerated. While protecting such a resource, conservation biologists have adopted a methodology and vocabulary of economics for the protection of diversity. So economic valuation of aquatic ecosystems besides other natural resources, has gained significance over the period of time. Moreover, economic valuation of a water body depends on its water quality, so better the water quality better will be the economic value. It is owing to this fact that Lake Mansar has been investigated for the abiotic and biotic characteristics of this lacustrine system. The book presents a detailed account of the ecological characteristics, threats and economic valuation of Lake Mansar so that environmental resources are proper allocated in order to improve the human welfare.