The book presents an extended idea on monitoring of natural radioactivity in drinking water as it is an important parameter for public health and Environmental studies. Along with cancer risk, chronic exposure to uranium and other radionuclides in humans has been linked to chronic lung disease, acute leucopenia, anemia, necrosis of the jaw and other effects. Activity concentrations of radionuclides, 235U, 238U, 226Ra, 40K, 232Th, and 137Cs in all ground water samples collected from various cities of Punjab Pakistan were determined using gamma ray spectroscopy and fission track method. The primary goal of this study is to investigate the levels of naturally occurring radionuclides in drinking water to calculate annual estimated dose to public. Radiological risk assessment was also calculated for mortality and morbidity risk that can provide basic information for consumers and competent authorities regarding the internal exposure risk due to drinking water intake.