We aimed to determine whether tissue transglutaminase (tTG) autoantibody positivity was associated with dietitian-assessed adherence to a gluten-free diet in pediatric patients with celiac disease and identify areas where adherence falters. We reviewed the records of children with celiac disease who had a standardized evaluation of adherence by a registered dietitian. A negative tTG value was not associated with good adherence (P = NS). Adherent and nonadherent children differed with respect to purposeful and accidental gluten exposure (P < 0.0001), knowledge (P = 0.003), cross-contact (P = 0.003), potential exposure via medications and cosmetics (P = 0.004), and potential exposure while at restaurants (P < 0.0001), but not with respect to potential exposure at school (P = NS). Based on our findings, we suggest that negative tTG levels are not necessarily indicative of good adherence to a gluten-free diet in pediatric patients with celiac disease. A separate assessment of adherence is needed focusing on knowledge, behavior while dining out, and intent to adhere.