Volume 82 describe reactions that involve one of the most common transformations in organic chemistry, namely, the pairwise combination of double bonded functional groups. The importance of this enormous family of reactions is a reflection of the spectacular diversity of precursors and products that can arise from appropriate modulation of reactivity of the partners and especially selection of reagents that dictate the outcome. The first chapter authored by Takeshi Takeda and Akira Tsubouchi describes the combination of carbonyl compounds in the presence of highly reactive, low valent titanium reagents in the classic McMurry reaction. The second chapter concerns the chemistry of highly-reactive, double-bonded functional groups, namely ketenes.