Gupta (Reservoir Induced Earthquakes, Elsevier, p 364, 1992) had dealt with the mechanism of reservoir induced/triggered earthquakes in detail. Incremental stress due to water load, pore fluid pressure changes and its role in triggering earthquakes and all related issues, are reviewed. The work carried out at Rocky Mountain Arsenal, Denver, Colorado, USA by Evans way back in 1966 laid the foundation to comprehend occurrence of RTS. He made use of Hubbert and Rubey’s (Bull Geol Soc Am 70:115–166, 1959) approach to explain the role of increased pore fluid pressure in triggering earthquakes consequent to fluid injections. The three most important consequences of filling of an artificial water reservoir are: (1) Elastic stress increases following the filling of the reservoir; (2) The increase in pore fluid pressure; and (3) Pore pressure changes due to fluid migration. Recent work indicates that both pore pressure and Coulomb stress on the seismogenic fault contributed to the triggered earthquakes at Lake Aswan, Egypt. The chapter shall also deal with ‘Induced or triggered earthquakes’, and ‘Rapid, delayed and continued seismicity’. This chapter is based on a recent publication (Gupta in Surv Geophys 43:619–659, 2022) where a global review of RTS has been provided.