Regulated transcription termination provides an efficient and responsive means to control gene expression. Rho-independent termination occurs through the formation of a RNA stem-loop which disrupts the RNA polymerase elongation complex1. In anti-termination, a mutually exclusive RNA structure is formed, and in some cases stabilised by ANTAR domains of proteins, preventing termination2. We have determined the crystal structures of the stabilising anti-terminator protein EutV in its apo form, to 2.5 Å resolution, and bound to the double stem loop RNA, 3.8 Å resolution. Our studies highlight the key interactions between conserved EutV residues and the RNA, as well as protein conformational changes undergone upon RNA binding. Thus proposing a general model for ANTAR domain anti-termination.