Modern methods of sample preparation have made it possible to analyze complete, packaged integrated circuits by transmission electron microscopy. TEM has two unique capabilities that cannot be matched by other characterization methods: 1) it is a direct crystallographic probe and 2) it has excellent spatial resolution, 0.2 nm. Small personal computers can be used to translate the micrographic data into statistical information that can be analyzed by non-TEM trained engineers. The data can also be stored in a MICROSTRUCTURAL DATABANK. The experimental data is automatically compared by the computer with previously established criteria. This methodology generates additional information that is used for quality and reliability assurance testing of integrated circuits. The method is applicable to devices that are removed from electronic systems after field operation, as well as to devices that have been lifetime tested. Two examples are described and discussed: aluminum grain size distribution analysis and silicide layer thickness measurement.