The use of fluorodeoxyglucose positron emission to-mography(FDG PET) scan technology in the manage-ment of head and neck cancers continues to increase. We discuss the biology of FDG uptake in malignant lesions and also discuss the physics of PET imaging. The various parameters described to quantify FDG up-take in cancers including standardized uptake value, metabolic tumor volume and total lesion glycolysis are presented. PET scans have found a significant role in the diagnosis and staging of head and neck cancers. They are also being increasingly used in radiation ther-apy treatment planning. Many groups have also used PET derived values to serve as prognostic indicators of outcomes including loco-regional control and overall survival. FDG PET scans are also proving very useful in assessing the efficacy of treatment and management and follow-up of head and neck cancer patients. This review article focuses on the role of FDG-PET com-puted tomography scans in these areas for squamous cell carcinoma of the head and neck. We present the current state of the art and speculate on the future applications of this technology including protocol de-velopment, newer imaging methods such as combinedmagnetic resonance and PET imaging and novel ra-diopharmaceuticals that can be used to further study tumor biology. The use of fluorodeoxyglucose positron emission to-mography (FDG PET) scan technology in the manage-ment of head and neck cancers continues to increase. We discuss the biology of FDG uptake in malignant lesions and also discuss the physics of PET imaging. The various parameters described to quantify FDG up-take in cancers including standardized uptake value, metabolic tumor volume and total lesion glycolysis are presented. PET scans have found a significant role in the diagnosis and staging of head and neck cancers. They are also being increasingly used in Many groups have also used PET derived values ​​to serve as prognostic indicators of outcomes including loco-regional control and overall survival. FDG PET scans are also proving very useful in assessing the efficacy of treatment and management and follow- up of head and neck cancer patients. This review focuses on the role of FDG-PET com-puted tomography scans in these areas for squamous ce We present the current state of the art and speculate on the future applications of this technology including protocol de-development, newer imaging methods such as combined magnetic resonance and PET imaging and novel ra-diopharmaceuticals that can be used to further study tumor biology.