The guest editors Marc De Batist and Oleg Khlystov dedicate this special double issue of Geo-Marine Letters, presenting contributions from the 10th International Conference on Gas in Marine Sediments (September 2010, Lake Baikal, Russia), to the memory of Mikhail Konstantinovich Ivanov. The author of this In Memoriam is Alexei Suzyumov, former staff member of UNESCO responsible for the TTR program.