Neutron diffraction is now established as a very reliable bulk and surface technique, with draft industrial standards in place and industrial take up increasing. The Strain Imager will be the new instrument for residual stress analysis of engineering components at the ILL, the worldTs most powerful steady state neutron source. Thanks to the improved flux of the new m = 2 supermirror guide (gaining a factor 3 to 5 on the existing guide), and improved optics the Strain Imager will increase the range of potential engineering applications by improving the resolution and shortening the measurement times. It is designed to allow measurements in components up to 2 metres in length and more than 500 kilogram weight (at a depth up to several centimetres), yet having a spatial resolution better than 0.5x0.5x0.5 mm3 . On the other hand, precise surface measurements will be standard, owing to the presence of collimators and to a positioning precision better than 50 μm. Special features include: a) the sample stage O the first to use a Stewart platform allowing 6 axis sample movement working in sample centric co-ordinates; b) a double- focusing bent Si monochromator, with very good resolution, very high intensity and a variable take-off angle from 55° to 125°; and c) a flexible optical system for the incident and diffracted beams. It will allow the use of combinations of different collimators and variable size slits for automated definition of the gauge volume.