In three separate manipulations, a group of children at risk for developmental coordination disorder (DCD; five males, seven females; mean age 11y 6mo [SD 6.8mo]who were at or below the 15th centile on the Movement ABC) and a group of typically developing children (TDC; seven males, five females; mean age 11y 3mo [SD 6.8mo]) judged the limit of their standing horizontal reach (HRmax) under two conditions in which actual HRmax differed. The manipulations were: (1) one-hand versus two-hand reach; and (2) standard versus short effective foot-length; and (3) rigid versus compliant support surface. For the foot-length and support surface manipulations (but not for the hand manipulation), children correctly judged that their actual HRmax differed in the two conditions (p < .05). On all three manipulations, TDC made significantly larger adjustments in their judgements than did children at risk for DCD (p < 0.05). The TDC group adjusted their judgements in the appropriate direction on all three manipulations, whereas the DCD group adjusted in the appropriate direction for the foot-length manipulation only. The results suggest that children at risk for DCD are less adept at detecting changes in the limits of their action capabilities.