The aim of this work package is to obtain the necessary materials, produce the necessary structures and samples and then generate the data necessary to determine the functional relationships between material internal length scales, test-piece external dimensions and mechanical test response. Advanced sample fabrication and characterisation techniques (such as SEM/EBSD, TEM/TKD) will be used to determine the critical length scales. The thermal stability of length-scale-enabled strength will also be studied as many industrial applications require working environments at high temperatures. In WP3, material systems will be selected that address important length-scales commonly present in relevant industrial sectors. Individual length-scales in each selected material system will be varied to cover the widest size range. The microstructure of selected samples will be characterised by partners using advanced techniques such as scanning electron microscopy (SEM), EBSD, TEM and transmission Kikuchi diffraction (TKD) to quantify the sizes achieved in each length-scale. Test specimens of different external dimensions will then be made from these materials. The reproducibility of test pieces will be quantified in order to calculate the uncertainties of subsequent test data. Indentation and mechanical testing of the manufactured specimens will be used to generate data at different testing length-scales. In this way, a comprehensive data matrix of test scale vs. specimen size vs. material microstructural length-scales will be generated from the selected materials. Finally, the stability of the length-scale-enabled strength will be investigated by obtaining test responses as a function of temperature. This will provide a measure of the activation energies of dislocation motion through the different barriers to motion, as well as providing a direct measure of the applicability of various strengthening mechanisms for use in high temperature applications.