Volume 68 of Organic Synthesis contains 31 checked and edited procedures representative of some of the most active areas at the frontier of organic synthesis. Although there is no single theme to this volume, the preparations are broadly compiled into six categories: simple one-and two-carbon synthons, chiral auxiliaries and sterocontrollled processes, functionalizations employing organometallic reagents, useful starting materials for constructing complex molecules, emerging reactions of potentially broad utility and cryptands with novel host-guest properties. The procedures published in this series are selected not only for their value in providing specific information to practitioners of synthesis but, in addition, they are intended to exemplify the highest experimental standards.