Tourism holds a place of prominence in economic development. The book aims to guide and support the readers through the complexities of the economic impact of tourism in the 21st century. It covers important principles and concepts that are supported by research and evidence from economics and other behavioural sciences. The degree of reliance of local economy on tourism has a statistically significant impact on the level of the capital outlays, transportation, Police protection, protection from natural disasters, Parks and recreation, financial administration and public expenditure. The book presents a comprehensive overview of history and global development of tourism, often considered the largest industry in the world today. The book is an outline on the economic, social and cultural issues of tourism in the Mountain region. It provides a detailed study on the economic impact in different regions of Sikkim for sustainable management and environmental protection.