Crystal centering is a key step in macromolecular X-ray crystallography experiments. A new method using image-processing and machine-vision techniques allows the centering of small crystals in the X-ray beam. This method positions crystals even when the loop is initially out of the camera's field of view and adapts to the difficulty of the experiment. The process has been tested on many diverse crystals with a 93% success rate when compared with manual centering.