The book offers an integrated overview of plant–pathogen interactions. It discusses all the steps in the pathway, from the microbe–host-cell interface and the plant’s recognition of the microbe to the plant’s defense response and biochemical alterations to achieve tolerance / resistance. It also sheds light on the classes of pathogens (bacteria, fungus and viruses); effector molecules, such as PAMPs; receptor molecules like PRRs and NBS-LRR proteins; signaling components like MAPKs; regulatory molecules, such as phytohormones and miRNA; transcription factors, such as WRKY; defense-related proteins such as PR-proteins; and defensive metabolites like secondary metabolites. In addition, it examines the role of post-genomics, high-throughput technology (transcriptomics and proteomics) in studying pathogen outbreaks causing crop losses in a number of plants. Providing a comprehensive picture of plant-pathogen interaction, the updated information included in this book is valuable for all those involved in crop improvement.