Routine transmission electron microscopy is recommended for all renal biopsies. However, most of the diagnostic lesions in renal pathology are 0.2 micron or larger, and are therefore visible by light microscopy. These lesions are difficult to evaluate in paraffin sections due to problems inherent in the method itself. Full utilization of the resolving power of the light microscope or high-resolution light microscopy is possible with resin (plastic) histotechnology. The replacement of conventional histotechnology by epoxy histotechnology allows the visualization of most subcellular structures needed for accurate diagnosis in renal pathology. Electron microscopy remains a very helpful tool for selected morphological problems.