In this study, the gentle SIMS (G-SIMS) concept has been applied to the crystallisable organic materials of Irganox 1010, caffeine, cholesterol, glucose, poly-L-lysine and bovine serum albumin. These are chosen to represent as wide a range of material types as possible. For each case, the G-SIMS spectra are considerably simpler than the static SIMS, enabling direct interpretation and identification. It is demonstrated that the amount of fragmentation in the mass spectrum may be controlled numerically and this information can be used to re-assemble the parent molecule. Wherever possible, the use of dual column ion beams is recommended to eliminate alignment requirements. Additionally, the total electron beam fluence should be kept below 6 x 10(18) electrons/m(2) to prevent electron damage. Crown Copyright (C) 2002 Published by Elsevier Science B.V. All rights reserved.