His research is concerned primarily with Soviet military, naval and strategic history from c. 1928-1945. He has recently published The Red Army and the Second World War with Cambridge University Press (2017), that examines the development of the Red Army from the late 1920s through to the end of the Second World War in Europe. He has also written on the nature and military effectiveness of the Soviet partisan movement in north-west Russia, 1941-1944, on the development of Soviet naval power in the Arctic up to the first months of the Great Patriotic War, and the significance of Allied Lend-Lease aid for the Soviet war effort during 1941-1942.