On invitation, the symposium “Correlation of the Precambrian”, Moscow, September 1975, and associated excursions to the Southern Urals and to the Belgorod region of the USSR were attended. In the Urals, stratotype area for the Riphean (late Precambrian), sections of the molasse-type Asha Group (Terminal Riphean), carbonate-clastic Karatau Group (late to Terminal Riphean), carbonate-clastic Yurmata Group (Middle Riphean) and carbonate-clastic Burzyan Group (Early Riphean) were examined. The groups are separated by unconformities or disconformities; in addition there are igneous intrusions dated at 1000-1100 m.y. between the Yurmata and Karatau Groups. The boundaries between the time divisions do not necessarily correspong with these group boundaries, but are based on changes in stromatolite assemblages. Diamictites seen in the Asha Group are possibly glacigene. Stratigraphically important stromatolites seen in the field include Balcalia, Minjaria, Gymnosolen and Inzeria; Minjaria occurs in well exposed bioherm series. The symposium involved lectures on Precambrian stratigraphy, palaeontology, petrology, tectonics, geochronology, and palaeomagnetism and ore deposition. The excursion to the Belgorod region showed open-cut iron mines in early Proterozoic banded iron formations first discovered as the Kursk Magnetic Anomaly. The ores are completely concealed by Mesozoic cover. Discussions with Russian geologists highlighted agreements and differences of approach to stromatolite study and classification. Core samples of terminal Riphean tillites from the Russian Platform were also displayed.