Minute holes have been drilled in germanium, molybdenum, iron, copper, silver, and tungsten carbide by a new technique for machining by electrolytic etching. The flow of current is localized by a nonconducting partition in the electrolyte. The partition may be a glass tube drawn down to a tip as small as one micron diam. A variety of shapes can be produced by moving the tip with respect to the work. Holes 20 microns in diameter and 1 mm deep have been drilled; shallow grooves 2 microns wide have been made. Localized plating has also been accomplished with the technique.