The invention provides an all electrical autonomous pipeline isolation tool for use in offshore and onshore pipeline isolation; the electrical autonomous pipeline isolation tool comprising a first part and a second part, the first and second parts being moveable relative to each other, the electrical autonomous pipeline isolation tool also comprising at least one sealing member which is moveable between an unset condition in which the sealing member is disengaged and the isolation tool is able to travel along inside a pipeline to a predetermined location; and a set condition in which the sealing member is engaged against an internal wall of a pipline such that a seal is formed between the sealing member of the isolation tool and the internal wall of the pipeline; the isolation tool being moveable between the unset condition and the set condition under action of the first part and the second part moving relative to each other. The all electrical pipeline isolation tool of the invention is controlled using an Extremely Low Frequency (ELF) communications system.Advantageously, the all electrical pipeline isolation tool of the invention is completely autonomous, without the necessity for a hydraulic pump and motor, hydraulic accumulator, hydraulic valving, hydraulic piston or hydraulic piping and hydraulic control system.