Gamma-ray bursts, powerful glares of high-energy that wash through the Universe once every day or so are, for a brief time, the brightest objects in the gamma-ray sky. The European Space Agency’s Integral gamma-ray observatory has observed several low-luminosity gamma-ray bursts, confirming the existence of an entire population of weaker bursts that, so far, had hardly been noticed. When it comes to detecting gamma-ray bursts (or GRBs), Integral is equipped with the most sensitive detector ever launched into space — the IBIS imager. Its field of view is extremely well shielded from any background radiation, making the detection of faint gamma-ray signals possible. Astronomers estimate that about 1400 GRBs per year occur but, as no one knows when and where they are going to appear, only some of them are detected. Integral detects an average of 10 GRBs per year and has collected data about 47 of them during four and a half years of operations.