A brief review of past British practice in engineering geological mapping is given. The paper follows the recommendations given in the Report on the Preparation of Maps and Plans in Terms of Engineering Geology prepared by a Working Party of the Engineering Group of the Geological Society.

A major division is made into small-scale maps generalised in content and made for regional and planning purposes, and large-scale plans relatively detailed in content and made for specific engineering purposes. Examples from present practice are illustrated and discussed. These include engineering geological maps, and engineering geological plans made at the reconnaissance, site investigation and construction stages of a project. Geotechnical plans, presenting a single engineering design parameter or a combination of a limited number of parameters, are illustrated for both the reconnaissance and site investigation stages of actual engineering projects.

After considering research in engineering geological mapping, likely future trends and desirable developments are discussed. It is considered that increasing use will be made of (i) engineering geomorphological mapping at the reconnaissance stage of investigation; (ii) site investigation mapping as part of conventional site investigations; (iii) geotechnical plan mapping for specific investigations and designs; (iv) engineering geological maps and plans specifically for use in urban situations by planners concerned with urban development.