The objectives were to describe the demographic characteristics of children with Fragile X syndrome (FXS) and to determine predictors of attendance at Fragile X (FX) clinics. Findings from the Community Support Network (CSN) and Our Fragile X World (OFXW) samples showed that children who attended FX Clinics were mostly male, high-school aged or younger, and white, non-Hispanic. Using logistic regression models, awareness about FX Clinic services, guardian education, and income (CSN), and child age, family income, and total number of co-occurring conditions (OFXW) were predictors of clinic attendance. Demographic and child characteristics accounted for a large portion of the explained variance. Importantly, symptom severity and parent knowledge about services were independent predictors beyond the demographic characteristics of families.