This study was performed to report the usage of sentinel lymph node biopsy (SLNB) in clinical stage I or II tongue cancer patients with cN0 necks seen over a 14-year period. Data were collected prospectively, and a retrospective analysis was performed of 41 patients with early stage oral squamous cell carcinoma of the tongue and a cN0 neck. Sentinel lymph node (SLN)-positive patients underwent elective neck dissection, whereas SLN-negative patients were kept under careful observation. Seven of the 41 (17%) patients enrolled in the study were found to have occult metastases. The patients were followed up for a mean duration of 92 months (range 60-144 months). The neck recurrence rate for SLN-positive patients was 0% and for SLN-negative patients was 3%. The authors recommend the routine use of SLNB in patients with early stage oral squamous cell carcinoma of the tongue and a cN0 neck. Furthermore, special focus should be placed on isolated tumour cells, as their presence is of high clinical relevance.