<p>Major insect vectors of plant viruses belong to the order Hemiptera and include aphids (Aphididae), whiteflies (Aleyrodidae), leafhoppers (Deltocephalinae), and mealybugs (Pseudococcidae) together with Thysanoptera (thrips). Conversely, psyllids (Psyllidae) together with spittlebugs (Cercopidae) and sharpshooters (Cicadellinae) are the major vectors of devastating diseases caused by plant pathogenic bacteria such as <i>Candidatus</i> Liberibacter spp. or <i>Xylella fastidiosa</i>. Host plant recognition by insect vectors is linked to plant pathogen transmission, including prealighting behavior, probing on superficial plant tissues, settlement, and stylet penetration to the target feeding tissues (mesophyll, phloem, or xylem tissues). This review will focus on how vector behavior modulates the transmission and spread of plant pathogens depending on their mode of transmission (nonpersistent versus persistent or noncirculative versus circulative). The role of phloem-feeders as vectors of plants viruses and their particular probing and feeding behavioral processes leading to the transmission of cuticula-borne and circulative viruses will be discussed. Furthermore, the behavioral activities linked to the transmission of phloem and xylem-limited bacteria by their insect vectors will be also described. This review also covers the likely retention sites of plant pathogens within the insect’s vector and how new biotechnological approaches can interfere with the transmission process. Finally, plant-mediated indirect and direct effects of plant pathogens on vector behavior and performance will be briefly covered.</p>