Recent progress in organic and LED structures, in photorefractive response in molecular ferromagnetism, as well as the ultrafast and large non-linear optical response in conjugated systems are attracting great interest from the scientific community. The discovery of fullerenes has added further impetus to this field. Two areas bear particular promise for the development of a new electronics based on SEM materials: the integration of organic materials into the planar silicon technology such as, for instance, the advances in "all organic" field-effect transistors (FET) and the new organic light emitting diodes (LED); and secondly the appearance of a totally new electronics in which photons, rather than electrons, carry the information and SEM materials act as switching devices. Both aspects and more are covered in this volume. The quality of the 52 contributions attests to the fact that this subject area has progressed from the level of a scientific curiosity to a mature field of materials science introducing important technological perspectives for electronic applications.