Release-recapture studies were used to assess the ability of male gypsy moths, Lymantria dispar (L.), to locate sources of (+)-disparlure across different distances and times from “emergence” (release) to presentation of pheromone sources. Two tests designs were used: (1) a single release point in the center of concentric circular arrays of traps and (2) multiple release points at different distances and directions from a single pheromone source. Mean percent recapture ranged from ca. 1% at 250 m from release to trap to 15-30% at 50 m or less, and from ca. 3% for males released 2 d before trap deployment to ca. 13% when releases and trap deployment were simultaneous. Percent capture fell off at cool temperatures (less than ca. 15° C), and males showed a tendency to be captured in traps upwind of release sites. Other weather-related variables did not significantly affect capture. Results of these studies will be used to develop models to estimate how mate-finding success affects the likelihood that incipient, introduced populations of invasive pests will become established.