Radiation monitoring has an important role in the nuclear and radiation safety of facilities that handle or produce radioactive materials. Measurements and posting of prevailing radiological status related to various structures, systems, and components are pertinent for compliance with regulatory requirements. As the human entry into the controlled areas of nuclear facilities is restricted to keep the exposures ALARA, various monitoring procedures, methods, and techniques are adopted to ensure appropriate assessment of radiological hazards. This chapter discusses conventional and state-of-the-art radiation monitoring systems that are required to be installed, commissioned, calibrated, and operationalized to evaluate the ambient radiation levels, besides the air, gas activity levels from the sampled analytes in the workplace. The importance of technical specifications for equipment selection for both fixed and monitoring systems, the equipment’s energy and measurement range, testing and calibration regime, the specificity of detection systems for measuring the radiologically significant radionuclides, the need for accident monitoring devices and gadgets personnel monitoring is underlined.