Parasitic plants are among the most problematic pests of agricultural crops worldwide. Effective means of control are generally lacking, in part because of the close physiological connection between the established parasite and host plant hindering efficient control using traditional methods. Seed germination and host location are critical early-growth stages that occur prior to host attachment, and provide promising targets for ecologically sound management of parasitic weeds. Knowledge of parasite-host interactions, particularly chemical cues that induce parasite seed germination and mediate host location, should facilitate the development of novel management approaches. In parasitic plants that attach to host roots - e.g., Striga and Orobanche spp. - seed germination is known to occur only in the presence of chemical stimulants released from plant roots. The recent finding that these same chemicals promote the colonization of beneficial fungi has potentially important implications for the control of parasitic plants. Far less is known about the early stages of parasitic plants that attach above-ground to host shoots - e.g., Cuscuta spp. Seeds of these parasites lack germination stimulants, and it was only recently shown that foraging C. pentagona seedlings use airborne cues to locate and select among hosts. We review research on seed germination and host location by the major parasitic weeds that attack agricultural crops, and discuss the implications of recent findings for the development of sustainable and effective management strategies.