The measure of the availability of food to individuals and their ability to access it is referred to as food security. It means that every human being has physical, economic and social access to food which is safe and nutritious. The dietary requirements of people should be met at all times to help them lead a healthy and active life. A major concern under this field is the availability of food to individuals of every class, region and gender without any bias. Food supply can be interrupted due to factors like shipping disruptions, economic instability, droughts, wars, fuel shortage, etc. The notable challenges to achieving food security are climate change, land degradation, population growth and global water crisis. This book is compiled in such a manner, that it will provide in-depth knowledge about the theory and practice of food security. Different approaches, evaluations, methodologies and advanced studies on this subject have been included herein. The book is appropriate for students seeking detailed information in this area as well as for experts.