Based on behavioral observations, the mating system of American Woodcock has been variously described as monogamous, a dispersed lek, or resource defense polygyny. Males perform elaborate mating displays that attract females to their display sites where copulations occur. We used microsatellite markers, developed for Ruffs (Philomachus pugnax), to assess paternity in American Woodcock. In 3 yr, we collected blood samples from 21 females and broods and 90 males. We found no evidence of multiple paternity within broods; paternity in all broods could be explained by 1 father. For 8 broods, we were able to infer probable fathers from males we sampled in the field. All 8 broods were found close to the singing site of the male or males that matched as possible fathers. Two males may have fathered 2 broods each, suggesting that polygyny may be a component of the woodcock mating system.