Recent developments in the chemistry of higher-order cyanocuprates are discussed, including the appearance and use of several new reagents prepared from copper(I) cyanide (CuCN) or copper(I) thiocyanate (CuSCN) and two equivalents of various organometallics. Numerous applications to synthetic problems in natural products chemistry are also described. 1. Introduction 2. New Synthetic Methodology 2.1. R2Cu(CN)Li2/CO 2.1.1. RCu(CN)Li/CO 2.2. (R3Si)2Cu(CN)Li2 2.3. RTRRCu(CN)Li2 2.3.1. Effects of Lewis Acids 2.4. RTRRCu(CN)LiM 2.4.1. RTRRCu(CN)Li[(n-C4H9)4N] 2.4.2. RTRRCu(CN)LiMgX 2.5. R2Cu(SCN)Li2 3. Uses of Higher-Order Cyanocuprates in Synthesis 3.1. Applications to Natural Products Total Synthesis 3.1.1. Epoxide Openings 3.1.2. Other Displacement Reactions 3.1.3. Conjugate Additions 3.1.4. 1,2-Additions 4. Concluding Remarks