This book gives the reader a ready made template for assessing the user friendliness of various available Agricultural Expert Systems (AES) all over the world. Information Efficiency Index developed in the study will help the scientists to ensure user friendliness of Agricultural Expert Systems. It has been established that Agricultural Expert Systems have more potential in the transfer of technology in terms of disseminating information to the users. The findings of the study of the authors revealed that the AES is more efficient in providing real time information and solutions to the field problems for making decisions by the prospective users in the absence of human experts. The study also discusses the socio-personal characteristics of potential users influencing the possibilities of functioning AES under the existing extension system. AES could not substitute human expertise in agricultural extension activities. Rather, it could be used to strengthen the existing extension activities as a supplementary extension tool in combination with human expertise, opine the authors.