The IEEE Transactions on Visualization and Computer Graphics (TVCG) November 2016 issue, contains a special section featuring papers presented at the IEEE International Symposium on Mixed and Augmented Reality 2016. Unfortunately, the welcome message contributed by the guest editors of this special section, Wolfgang Broll, Hideo Saito, and J. Edward Swan II, was accidentially omitted. The November 2017 issue of TVCG is a special issue featuring papers presented at the IEEE International Symposium on Mixed and Augmented Reality 2017. Under similar circumstances as mentioned above, the welcome message contributed by the guest editors of this special issue, Wolfgang Broll, Holger Regenbrecht, and J. Edward Swan II, was accidentially omitted. We include both messages in the following, with apologies to the guest editors and our readers. Dieter Schmalstieg Associate Editor-in-Chief, TVCG For information.