Drought indices have been devised for identification of drought and characterization of its severity. Using drought indices, the duration, intensity and areal extent for each drought episode can be defined. They can be used to describe all types of droughts (that is meteorological drought, hydrological drought, agricultural droughts and socioeconomic drought). According to the type of drought, the appropriate drought index is selected. Drought indices are composite numerical figures incorporating mainly values of hydrometeorological indicators. The most popular drought indices presented in the report and applied in the participating countries in the MEDROPLAN project include the SPI, the PDSI, the method of Deciles, the recently developed RDI and others. Crucial elements in the procedure for calculating drought severity by using drought indices are the time step adopted and the threshold of each index selected. During the project a common methodology for applying drought indices for monitoring and assessment of droughts and estimation of drought risk was devised and applied to all case studies.