Terra Sulis uses Satellite Remote Sensing (RS) and Geographical Information Systems (GIS) to compile, manage and analyse data sets for environmental applications. We use a lot of open data that are freely available such as the Sentinel-2 optical satellite imagery, Environment Agency LiDAR, and data sets available from government agency sources such as Natural England, The Forestry Commission and Ordnance Survey. These data are generally available under the Open Government Licence (OGL). The key thing about them is that they are digital and can be processed by computers and they are open to use, under certain conditions. Some of the methods we employ are simple digital mapping, whilst others are based on machine learning and bespoke computer processing. Terra Sulis strives to add value to these open data resources and to make them accessible as derived information products. In some cases we have to charge a reasonable handling fee to make them available.