Background: Thoracic mobility in the sagittal and horizontal planes are key requirements in the sport of surfing; however to date the normal values of these movements have not yet been quantified in a surfing population. Objectives: To develop a reliable method to quantify thoracic mobility in the sagittal plane; to assess the reliability of an existing thoracic rotation method, and quantify thoracic mobility in an elite male surfing population. Design: Clinical Measurement, reliability and comparative study. Methods: A total of 30 subjects were used to determine the reliability component. 15 elite surfers were used as part of a comparative analysis with age and gender matched controls. Results: Intraclass correlation coefficient values ranged between 0.95-0.99 (95% CI; 0.89-0.99) for both thoracic methods. The elite surfing group had significantly (p ≤ 0.05) greater rotation than the comparative group (mean rotation 63.57° versus 40.80°, respectively). Conclusion: This study has illustrated reliable methods to assess the thoracic spine in the sagittal plane and thoracic rotation. It has also quantified ROM in a surfing cohort; identifying thoracic rotation as a key movement. This information may provide clinicians, coaches and athletic trainers with imperative information regarding the importance of maintaining adequate thoracic rotation.