Hepatitis B infection is a major public health problem. Approximately two billion people worldwide have been infected with hepatitis B virus (HBV) during their lifetime. In some patients Hepatitis B may get converted into a dormant stage and get reactivated during immunosupression like chemotherapy. Hepatitis B complicates management of cancers as reactivation of hepatitis B not only increases morbidity and mortality but also prolongs chemotherapy and may result in inadequate outcomes. Several approaches have been developed to prevent reactivation of hepatitis B in cancer patients. One such approach is active immunization of all cancer patients. The present study has been done to understand the problem of hepatitis B in cancer patients and to evaluate the efficacy of vaccination in prevention of hepatitis B in cancer patients.Dr Waseem Dar has completed his MBBS from Govt Medical College Srinagar in 2010 and his MD in Internal Medicine from Sheri Kashmir Institute of Medical Sciences in 2014. He is an active academician beside being a clinician. He has done lot of research and has large number of publications. Besides he is on editorial board of many reputed journals.