A wind turbine blade (2) comprising an outer shell (6) incorporating a metallic foil component (20), a conductive blade component (12) in-board of the metallic foil component (20), and a fabric sheet assembly (22) positioned between the metallic component (20) and the conductive blade component (12). The fabric sheet assembly comprises: one or more non-conductive fabric sheets (28, 30) which define first and second outer surfaces (24, 26) of the fabric sheet assembly (22); and at least one conductive thread stitch (34) penetrating a depth of the one or more fabric sheets (28, 30) and being exposed at the outer surfaces (24, 26); thereby to enable equipotential bonding between the conductive blade component (12) and the metallic foil component (20).