There are three types of membership in the RAS: full members (academicians), corresponding members, and foreign members. Academicians and corresponding members must be citizens of the Russian Federation when elected. However, some academicians and corresponding members were elected before the collapse of the USSR and are now citizens of other countries. Members of RAS are elected based on their scientific contributions – election to membership is considered very prestigious. In the years 2005–2012, the academy had approximately 500 full and 700 corresponding members. But in 2013, after the Russian Academy of Agricultural Sciences and the Russian Academy of Medical Sciences became incorporated into the RAS, a number of the RAS members accordingly increased. As of November 2016, after the last elections, there were 944 full members and 1159 corresponding members in the renewed Russian Academy of Sciences. Earlier, in winter 2015/2016, the Academy assigned the so-called RAS Professors (493 scientists), subordinated to the regular members and considered as possible future candidates for membership; 104 professors were elected already in autumn 2016 and will henceforth be titled as “RAS professor, corresponding member of the RAS”.