Abstract: A fusogenic liposome comprising a lipid bilayer comprising a plurality of lipid molecules having 14 to 24 carbon atoms, wherein at least one of said lipid molecules is functionalised with a first functional group of a specific binding pair capable of binding to a complementary second functional group of said binding pair; and optionally further comprising an immune system activating agent functionalised with a complementary second functional group of said binding pair bound to said first functional group is provided. Methods of treatment of cancer using the fusogenic liposome are also provided.