According to the National Sleep Foundation’s Sleep in America Poll, U.S. adults sleep between 6.7 to 7.3 hr every night, which has decreased by approximately 2 hr per night since the 19th century (National Sleep Foundation, 2016). Inconsistent or insufficient sleep can be costly for business, impacting leadership decision making/judgment, interpersonal relations, absenteeism, presenteeism, safety, productivity, and health (Gaultney & Collins-McNeil, 2009; Mills et al., 2007; Rosekind et al., 2010). Daytime sleepiness can be dangerous, and inadequate sleep is a known health hazard resulting in fatigue that can impair both performance and social functioning. In light of existing research on the effects of insufficient sleep on work performance, this study investigated the relationship between self-reported sleep quality and quantity (Stress Profile) of leaders with a concurrent evaluation of relationship skills by their manager and others (direct reports and peers) on a measure of emotional and social competence. Regression analyses indicated that leaders who reported poor quality and quantity of sleep were rated significantly lower on interpersonal effectiveness after controlling for gender and perceived work/life stress by their direct reports and peers but not by their manager.