The overall aim of this work package is to develop metrology for identification, localisation and quantification of chemical species and defects at buried interfaces, principally using the new 3D nanoSIMS instrument. The instrument is equipped with a hybrid ToF and Orbitrap HF analyser, the former giving fast analysis, but low mass resolution (10 000) and the Orbitrap HF providing slow analysis and ultra-high mass resolution (>100 000). The instrument is also equipped with a Bi nanoprobe ion beam capable of 80 nm resolution, but causing damage in organic materials, and a new argon cluster ion source with an aim to achieve sub-micron resolution imaging. This work package will develop the new metrology essential for this powerful instrument; in particular, optimisation of the different operating modes for the stakeholder community. Methods will also be developed for topographic samples such as medical device stents.