Michael B. Matthews1, Edward P. Vicenzi2, Silvia Richter3, Xavier Llovet4, Jan Dellith5 and Miran Ceh61 AWE Plc., Aldermaston, Reading RG7 4PR, Great Britain2 Smithsonian Institution, Museum Conservation Institute, 20746 Suitland, MD, U.S.A.3 RWTH Aachen, Gemeinschaftslabor für Elektronenmikroskopie (GFE), 552074 Aachen, Germany4 Universitat de Barcelona, Scientific and Technological Centres, Lluís Solé i Sabarís 1-3, 08028 Barcelona, Spain5 Leibniz Institute of Photonic Technologies, Dept. Instrumental Analytics, 07745 Jena, Germany6 Jožef Stefan Institute, Department for Nanostructured Materials, Centre for Electron Microscopy, Jamova cesta 39, 1000 Ljubljana, SloveniaPrefaceThis volume of the IOP Conference Series: Materials Science and Engineering contains papers from the 15th Workshop of the European Microbeam Analysis Society (EMAS) on Modern Developments and Applications in Microbeam Analysis, organised in conjunction with the 7th Meeting of the International Union of Microbeam Analysis Societies (IUMAS), which took place from the 7th to the 11th of May 2017 at the Konzilgebäude, Konstanz, Germany.The primary aim of this series of workshops is to assess the state-of-the-art and reliability of microbeam analysis techniques. The workshops also provide a forum where students and young scientists starting out on a career in microbeam analysis can meet and discuss with the established experts. The Konstanz EMAS-IUMAS meeting was organised within the usual EMAS format, comprising invited plenary lectures by internationally recognized experts, poster presentations by the participants and round table discussions on the key topics led by specialists in the field. The workshop was organised in collaboration with the Microprobe Division of the German Physical Society (DPG). IUMAS member societies co-funded 16 Early Career Scholars to attend the meeting in Konstanz. The technical programme included the following topics: pushing the limits - electron probe microanalysis, modelling, detector technologies, surface characterisation, cathodoluminescence, pushing the limits – general, and their applications.As at previous workshops there was also a special oral session for young scientists. The best presentation by a young scientist was awarded with an invitation to attend the 2018 Microscopy and Microanalysis meeting in Baltimore, Maryland. The prize went to Ery C. Hughes, University of Bristol (UK), for her presentation entitled: “Low EPMA totals of hydrous basaltic glass: effect of sub-surface charging” (by E.C. Hughes, B. Buse and S.L. Kearns).Six half-day pre-meeting courses were held covering the following areas of microbeam analysis: introduction to EBSD, advanced EPMA including CalcZAF, electron microscopy maintenance, Monte Carlo simulation using PENEPMA, Advanced spectral imaging, mapping and phase analysis, Monte Carlo simulation, and introduction to atom probe.The continuing relevance of the EMAS-IUMAS meetings and the high regard in which they are held internationally can be seen from the fact that 93 posters from 20 countries were on display at the meeting and that the participants came from as far away as Australia, Brazil, Canada, China, Japan, and USA. A selection of participants with posters was invited to give a short oral presentation of their work in three dedicated sessions. The EMAS Young Scientist Poster Award was awarded with an invitation to participate in the 25th Australian Conference on Microscopy and Microanalysis (ACMM 25) in 2019 in Melbourne, Australia. The prize was awarded to Dr Joshua Einsle, University of Cambridge (UK), for his contribution entitled: “The potential for mineralogical mapping through machine learning” (by J.F. Einsle, R.J. Harrison, B. Martineau, I. Buisman, A.M. Piotrowski, S.M. Collins, Z. Saghi, D. Johnstone, A. Eggerman and P.A. Midgley). The EMAS Workshop Poster Prize was given to Nicole Wollschläger, Bundesanstalt für Materialforschung und –prüfung (BAM) (DE), for her contribution entitled: “Characterisation of porous TiO2 nanoparticle films using on-axis TKD in SEM - a new nano analytical tool for a large scale application” (by N. Wollschläger, L. Palasse, I. Häusler, E. Ortel, K. Dirscherl and V.-D. Hodoroaba).This proceedings volume contains the full texts of 8 of the invited plenary lectures and of 13 papers on related topics originating from the posters presented at the workshop. All the papers have been subjected to peer review by a least two referees.