A detailed investigation of the various physical properties of the interfacing of a Si(Li) energy dispersive spectrometer (EDS) to a transmission electron microscope (TEM) has shown that for a Philips 301 TEM the best physical location for the detector is in the port usually accomodating the anticontamination cold finger and as close to the sample as possible. The optimum tilt of the sample has been found to be 36° and the optimum voltage is actually the highest available. By the use of a strong prefield objective lens, it is possible to obtain reliable quantitative elemental analysis from areas as small as 25 nm diam. Various correction schemes and the use of a powerful profile fitting technique allow for recovery of spectra with overlapping peaks under the worst possible conditions. Using a straightforward analysis scheme the data may then be reduced to elemental composition with an accuracy and precision on the order of 1%, which is far better than has been reported in literature for TEM−EDS thus far. All of this was obtained with no loss in the nominal high resolution and diffraction capabilities of the TEM.