Breeding pair surveys for Harlequin Duck were done on 242 km of 18 streams during May and June, 1994; a total of 57 Harlequins (32 males and 25 females) were seen on 9 streams. Brood surveys were done on 245 km of 14 streams during July and August, 1994; a total of 82 Harlequins (15 females, 67 young in 15 broods) were seen on 8 streams. Harlequins were reported on 2 additional streams. Reproductive success, on streams surveyed both for pairs and broods, averaged 0.33 broods per female. Average brood size at or near fledging (Class III) was 4.00. Breeding was confirmed on Grave Creek (Fortine) for the first time in 1994; 4 adult ducks were seen of Swift Creek, more than previously reported. We found ducks on Sullivan Creek in 1994, where they were not found during 1993. No birds were seen during pair (May) or brood (August) surveys on Big Creek (Koocanusa), which had Harlequins in 1990, nor on a brood survey of the North Fork of the Blackfoot River, where ducks were seen in 1993. We continued banding Harlequin Ducks in the Flathead and Clark Fork drainages. Thirty-five Harlequins (7 adult males, 7 adult females, and 19 juveniles) were marked on 7 streams. This brings the total number of Harlequin Ducks banded since 1991 to 1994 (29 adult males, 41 adult females, and 122 juveniles). We observed 11 birds previously marked as adults on streams. Additionally, we found 9 adult females marked as juveniles in 1992 on the streams where they were seen in 1994. The banding program, while small in scale for waterfowl, is providing a significant tool for local monitoring and identifying coastal areas where Montana breeding birds molt and winter. Two noteworthy movements were detected in 1994: a male marked on McDonald Creek, Glacier National Park, on 6 May 1993, was captured on Hornby Island, along the southeast coast of Vancouver Island, British Columbia on 5 August 1993 and again on 4 August 1994. On 11 August 1994 a male, marked as a juvenile on McDonald Creek exactly two years earlier, was captured at Shelter Point on the coast south of the Campbell River, on Vancouver Island, B.C.