The choice of appropriate MR pulse sequences to highlight a particular pathology to best advantage is not always straightforward. In this study of intracranial haemorrhage, tissue relaxation times measured in vitro were entered into a computer program which calculated the signal intensity of each tissue (brain, blood, CSF, and bloody CSF) for all possible echo (TE) and repeat (TR) times. Analysis of graph plots of the results enabled the selection of pulse sequences which gave optimal separation of the signal intensities of intracranial haemorrhage from those of normal intracranial contents. The sequences thus chosen were used successfully in the imaging of patients with intracranial haemorrhage.