Extraterritorial forays are one specialized tactic that females use to obtain extrapair copulations (EPCs). By radio-tracking female hooded warblers (Wilionia citrina) during the breeding season, we found that females made covert forays onto neighboring territories. Almost 80% of females made extraterritorial forays during their fertile stages, but none visited territories during the nonfertile (incubation) stage, which is consistent with the extraterritorial foray hypothesis. Females that left their territories visited from one to four neighboring territories, and they intruded at a rate of 0.6 territories/h. The propensity of females to foray from their territory did not correlate with body size or age of the social mate. One female that left her territory obtained an extrapair fertilization. Females may use forays to assess male quality as well as participate in extrapair copulations. An alternative hypothesis for extra-territorial forays is that females may foray onto neighboring territories to obtain food during the energetically stressful period of egg production. The extraterritorial foray hypothesis and foraging hypothesis may not be mutually exclusive. Females may obtain benefits of foraging while at the same time assessing males for EPCs. Extraterritorial behavior of female birds may be more common than previously believed and in many cases may only be ruled out through radio-tracking