Chrosomus cumberlandensis (Blackside Dace) is a threatened stream fish endemic to the upper Cumberland River drainage in Kentucky and Tennessee. Little is known about the movement patterns of this species. Acquiring an understanding of baseline dispersal patterns is necessary to inform management and recovery actions. We tagged 653 Blackside Dace with visible implant elastomer injections in the Big Lick Branch and Rock Creek watersheds of southeastern Kentucky to determine the frequency, spatial extent, directionality, and environmental correlates of dace movements. We recaptured dace from February 2003 through March 2004 using baited minnow traps. Most tagged dace (81% in Big Lick Branch and 58% in Rock Creek) were recaptured within the same 200-m stream reach where tagging occurred. However, several individuals moved considerable distances from the original tagging site, including the first documented intertributary movement for this species. Mean (± SD) distances moved upstream in Big Lick Branch (148 ± 138 m) and Rock Creek (733 ± 1259 m) were not significantly different from mean distances moved downstream (77 ± 29 m and 314 ± 617 m, respectively). However, the mean overall distance moved was greater in Rock Creek, a longer stream than Big Lick Branch. The spatial arrangement of traps in both watersheds likely produced a distance-weighted bias such that we slightly overestimated the frequency of short-distance movements and underestimated the frequency of long-distance movements. Our results for Blackside Dace are consistent with a number of other studies that found stream fish populations composed of a large sedentary group and a smaller mobile group. The demonstrated ability of Blackside Dace to move into and between tributaries will remain vital for long-term population viability, and emphasizes the importance of maintaining suitable corridors within and among Cumberland River tributary streams.