Previous Cold Spring Harbor Symposia have addressed many different aspects of RNA biology such as Mechanisms of Transcription (1998), The Ribosome (2001), Epigenetics (2004) and Regulatory RNAs (2006). The 84th Cold Spring Harbor Symposium focused on RNA Control & Regulation and provided a current synthesis of the enormous progress in our understanding of RNA's influence on cells and organisms and how, when aberrant, its effects may contribute to the progression of disease. It is rare to find such a wide-ranging perspective on this topic in one volume and this collection of papers will be valuable to investigators in many fields. The topics covered at the meeting included: RNA-Based Structures; RNA Modifications; Nuclear Localization of RNA; Quality Control & Editing; RNA & Gene Regulation; Cotranscriptional Splicing; Intron/Exon Boundaries; Alternative Polyadenylation; Transposon Control; Small Noncoding RNAs; Long Noncoding RNAs; RNA & Development; Membrane-Less Organelles; Phase Separation; RNA-Based Diseases; and Novel RNA Functions. Numerous speakers participated in interviews during the course of the Symposium week and this volume includes transcripts of those discussions and the Dorcas Cummings lecture, for the general public, which was given by Dr. Jennifer Doudna.