Recent developments in the use of near-field scanning optical microscopy-based techniques to monitor and image physical processes related to device function in thin film organic materials are surveyed. By combining subwavelength optical probes with electro-optical spectroscopic techniques, methods have been developed for measuring the dynamics, spatial variation, and diffusion of energy and charge carriers in organic electro-optical devices. Materials investigated include polymer thin films, polycrystalline and amorphous (glassy) organic films, liquid crystalline materials, and molecular semiconductor heterostructures. (C) 2000 American Institute of Physics. [S0021-9606(00)70416-8].