Effective chemical synthesis of a complex natural product in a laboratory flask requires careful planning so that the smallest possible number of reaction steps is used and they all occur at high chemical yields. These efforts can be thwarted when key strategic steps (forming important chemical bonds or establishing stereogenic centers) are unselective-that is, they furnish undesired reaction products instead of or in addition to the one needed to complete the synthetic sequence. To overcome these challenges, new types of transformations are sought that proceed with high selectivity under the mildest possible conditions. On page 261 of this issue, Ippoliti et al. (1) describe the use of a new class of reactive intermediates, cyclic allenes, in the enantioselective synthesis of the alkaloid lissodendoric acid A. This synthesis highlights how cyclic allene chemistry can work in tandem with other methods to obtain daunting products in a selective fashion. © 2023 American Association for the Advancement of Science. All rights reserved.