Grit, defined as passion and perseverance for long-term goals, predicts success in a number of social domains. The present two studies examined grit and its subscales, and how these relate to both adaptive and maladaptive personality traits pertaining to success. For Study 1, based on data from 249 participants, results indicated that grit was correlated positively with proactive personality, personal growth initiative, and competitiveness, and the perseverance subscale also was correlated positively with self- and other-oriented perfectionism. The findings of Study 1 led us to further explore the dark aspects of grit in Study 2: based on data from 222 participants, results indicated that grit was correlated negatively with Machiavellianism, hypercompetitiveness, and most forms of narcissism but positively correlated with adaptive grandiose narcissism. Collectively, results reveal grit to be a positive, adaptive trait but raise questions regarding the perfectionistic tendencies of gritty individuals and the unitary nature of the construct.