Description:This edited work contains eight extensive, review-type contributions by leading scientists in the field of synthetic metals. The authors were invited by the organisers of the International Conference on Science and Technology of Synthetic Metals '98 (ICSM'98) to review the progress of research in the past two decades in a unifying and pedagogical manner. The present work highlights the state-of-the-art of the field and assesses the prospects for future research.