OBJECTIVE: To evaluate the impact of administration context (embedded versus stand-alone) on the reliability and validity of the FACT Head and Neck Symptom Index (FHNSI). METHODS: Ninety-eight patients with head and neck cancer were randomized to one of two assessment conditions to evaluate the FHNSI’s context (items administered embedded within the FACT-H&N or as stand-alone scale) and order of administration in the battery. RESULTS: Planned comparisons on the item and scale levels revealed no systematic order or context differences. The embedded and stand-alone versions of the FHNSI showed high internal consistency (Cronbach’s alpha 0.79-0.87). Correlations were high between the FHNSI versions and the physical and functional well-being scales of the FACT-H&N (0.70-0.84) and measures of pain intensity (-0.73, -0.74) and depression (-0.71, -0.74); moderate to large with the Performance Status Scale for Head and Neck subscales (PSS-HN; 0.46-0.71); and low with an anxiety measure (0.30, 0.34). Both FHNSI versions differentiated patients grouped by performance status (p < .0001, p < .0001) and global rating of change (p < .0001, p < 0.01). The FHNSI's minimally important difference range was 3-4 points. CONCLUSION: The FHNSI is a reliable and valid symptom index, which can be administered alone or scored using items embedded within the FACT-H&N.