A method of depositing or etching a micro- or nano-scale pattern on a work piece is disclosed, including the steps of: (a) placing the work piece in an electrochemical reactor in close proximity to a patterned tool; (b) connecting the work piece such that it is the anode if is to be etched or the cathode if it is to be deposited, and the patterned tool such that it is the counter electrode; (c) pumping electrolytic fluid necessary for the electrolytic operation of the cell formed between the two electrodes; and (d) applying a current across the electrodes to etch or deposit the work piece.