Helicopter flights may affect wildlife, but habituation to disturbance is possible. We tested the hypothesis that mountain goats in a population exposed to helicopter flights for over 40 years have habituated to helicopter traffic. We contrasted behavioral responses of marked mountain goats to helicopter flights during 2 time periods (1995 vs. 2005–2009). The proportions of helicopter flights resulting in no/light, moderate, or strong disturbance were similar in 1995 and 2005–2009. Horizontal distance was the main factor determining mountain goat responses to helicopter flights; goats had a very high probability (>0.8) of being moderately and strongly disturbed (moderate: moved 10–100 m, alert for 2–10 min; strong: ran >100 m, alert for >10 min) when they were approached within 500 m by helicopters. We found that mountain goats only very slightly habituated to helicopter flights during a period of 10–15 years of repeated helicopter traffic. Because disturbance from helicopter flights has remained high, and in view of the continuous increase of helicopter traffic in mountainous habitat, we recommend helicopter flights do not approach closer than 1,500 m from mountain goat groups. © 2013 The Wildlife Society.