This site is dedicated to sharing knowledge on mass spectrometry imaging (MSI, also termed imaging MS or MS imaging). In brief, this is an emerging field in science allowing true label-free molecular imaging of flat samples, e.g. biological tissue sections. On this site you find a lot of information on matrix-assisted laser desorption/ionization mass spectrometric imaging (MALDI MSI), but also other techniques including SIMS, DESI, LA ICP MSI, IMC and more are represented. The software section hosts multiple programs for image acquisition and processing, including BioMap. Since 2012, this site also hosts information from the COST action on MS imaging and on the imzML data format. As of the 2017, the site is home of and operated by the Mass Spectrometry Imaging Society.