 Lark and Durham were to be kept completely separate, with Gjems-Onstad as their only mutual connection.Durham's mission was to influence the moral of the enemy, mainly through distributing brochures (an estimated 115,000 copies in total) and posters (an estimated 257,000), while also to cause irritation by minor sabotage.The brochures were chiefly distributed in the enemy's quarters, and the posters were put up throughout Trondheim.