A collection of topical and mostly critical reviews written by professionals who are working or have been working in this and related fields, this book intends to provide a complete, ordered and concise summary of what is known (or not known) about carbyne at this date. The authors have tried to be critical of overstated results and expectations and have made an effort to provide a balanced approach to the controversial topic. The book provides a sound approach to this elusive carbon allotrope. This book will be of interest to research scientists (both experimentalists and theoreticians), postgraduate and graduate students working in the field of chemistry and physics of carbon (including diamond and diamond-like materials, graphite intercalation compounds, fullerenes, carbon nanotubes and related areas), conjugated and/or bio-polymers, and one-dimensional molecular systems.