This appendix has information about using various text editors efficiently with MathBook XML source. The choice of an editor that suits you is a big part of being a productive author. Despite not being open source, we are partial to Sublime Text, due to its unlimited trial period, reasonable licensing (cost and terms), range of features, and cross-platform support. So we lead with Sublime Text, but also include Emacs and XML Copy Editor. A summary table of schema-aware editors can be found at Section 5.7.