Abstract: The reactor pressure vessel (RPV) is generally considered to be the most important component in a nuclear power plant in terms of safety and overall structural integrity. An RPV is not considered to be a replaceable component, and, thus, the monitoring of the material toughness properties during long-term operation is of crucial importance. RPV surveillance programs are almost always applied for such monitoring, and the design of the capsules, operations to install and remove capsules, and testing of irradiated specimens is governed by international/national codes and standards and can differ between individual reactor designs, as well as requirements/methodologies used in different countries. Results from testing actual RPV material specimens irradiated in the surveillance capsules serve to the assessment of current and future degradation levels of RPV material toughness properties. Thus, the surveillance program results provide needed input for RPV integrity evaluations and future operating lifetime determination.