There is a growing interest in the development and deployment plan of Small and Medium Sized Reactors (SMRs) which can be seen through the numerous concepts that are under design certification and the several units that are under construction, the expanding of potential markets in developing countries, and the increasing demands from the Member States on the supports and role of the International Atomic Energy Agency (IAEA). The paper summarizes the status of SMRs designs that are under development globally with the aim to give a broad perspective. It presents generic technical issues and prospect of SMRs, the advantages, challenges and parameters that potential markets take into consideration with regard to the introduction of the first nuclear power plant. Some of the issues to be addressed are economics, licensability, operational performance, waste management, safety and security, proliferation resistance and financing scheme. In the post-Fukushima era, the incorporation of the preliminary lessons learned from the accident into the SMR designs is a priority. In the end, the IAEA program on the common issues and technology of SMRs are highlighted with the purpose to facilitate countries with interest in SMRs.