Laser intensity images, created by visualising the amplitude of each returned laser pulse as a greyscale image, are often ignored when working with the results of lidar surveys. Fortunately a growing body of research demonstrates the value and uses of intensity imagery. In this paper (focusing on data collected by Optech instruments) we summarise the problems inherent in collecting and using intensity data, review examples of its use in a variety of environmental disciplines and discuss experiments to determine its potential uses for archaeological studies.