Plant pathogenic geminiviruses have been proliferating world-wide and have, therefore, attracted considerable scientific interest during the past three decades. A widespread occurrence and vast spreading of geminivirus, resulting in yield losses of economically important food and fibre crops, poses a serious threat to sustainable agriculture. The major concerns about the frequent evolution and recombination of new viruses or strains lead to failure of resistance over time and space. This book reviews recent developments in the study of geminiviruses and the progress made in this field.