This series consists of the minutes of the Home Ports Defence Committee (HPDC), later the Home Defence Committee (HDC) of the Committee of Imperial Defence.
Topics covered include fixed defences at defended ports (including defence of the Channel Island ports), harbours, the defence of vulnerable points, air attack and air defence, coal supplies, cable landings, government offices, telegraphs and communications, oil and petrol stores and the role of the Territorial Army.