Forest plays a multi-dimensional role in maintaining many global processes. Therefore, it's sustainable management is crucial for long term survival of human beings. The measurement of sustainability is tricky and complex. Such measurement benefits forest management unit to attain a certification label which will authenticate the products coming from such units to the global wood market. This certification procedure involves hierarchical evaluation of many parameters which are defined in a vague manner using crisp verbal conditions. Currently Multi-Criteria Decision Making approaches like Ranking, Rating and Anlaytical Hierarchical Process (AHP) are generally used for evaluation. However, these approaches are numerical in nature and hence poses a compensation problem for an ecologist as in the nature the environmental interactions are very fuzzy. Also the current methods do not have provision to incorporate expert knowledge, attitude and confidence. This book addresses all these issues and provides solution using Fuzzy AHP, Cognitive Mapping and Fuzzy Logic, with examples. This book can also be used as a text book for master degree courses in Forestry, Ecology & RSGIS.