A method of imaging a histological sample is provided which comprises stimulating autofluorescence in a sample using electromagnetic radiation of wavelength 750 nm. Detection of the autofluorescence is undertaken by a CCD camera, typically with an excitation filter of 510 nm disposed between the camera and the sample. The weak signal from autofluorescence is reinforced by manipulation of data acquired by the camera. Autofluorescence is detected from an upper face of the sample, an upper layer of the sample removed and a next face of the sample imaged. These steps are repeated to obtain information on autofluorescence throughout the sample. The method enables detection of features for virtually any thickness of slice, and in particular slices can range from 50 m to 1 m, with the method generally being used to analyse slices of thickness 5-1 m. There is also provided a method of preparing a histological sample for use in the above method, and apparatus (10) for imaging autofluorescence in histological samples.