The RNA world hypothesis is founded on the idea of an RNA replicase, or self-replicating RNA molecule, and presupposes the later emergence of ribozymes capable of catalyzing the synthesis of peptides. The recent demonstrations of ribozyme-catalyzed template-directed primer extension, and of ribozyme-catalyzed amide bond synthesis, confirm the plausibility of the RNA world, and highlight the steps that remain to be demonstrated in the laboratory.