We have developed a system of highly compliant, low thermal conductance electrical interconnects c for cryogenic detector applications. The arrays of microwires are metallic, thin-film electrical leads supported by a layer of polyimide, capable of spanning the thermally isolated gap between the detector array and the low temperature heat sink in cryogenic detector assemblies. The low thermal conductance of the microwires enables detector thermal isolation without the need for conventional hard wiring, such as soldered manganin (an alloy of nickel, manganese, aluminum, iron, and copper) or stainless steel. Designed for compactness, an array of 30 microwires can be designed to fit on a silicon chip less than one-half of I cm 2 in total surface area. We describe techniques for fabrication of arrays of polyimide microwires with several different types of conductive traces, both superconducting and normal metals. Mechanical elongation of 20% beyond the design length resulted in an increase in aluminum microwire resistance of only 1%, and no stress to the polyimide. Cryogenic elongation yielded no change in electrical or mechanical properties. The thermal conductivity of a single, aluminum microwire is found to be 3.8 X 10(-8) W / K at 4.4 K and 1.1 X 10(-8) W/K at 2.2 K.