"no excuse" -- I would respectfully disagree here. There are lots of very smart people who have worked on Qt. Really, some insanely good C++ programmers have worked on that project. I have no doubt that they have discussed changing class QString to use UTF-8 internally. To be clear, probably QChar would also need to change, or a new class (QChar8?) would be needed, in parallel to QChar. I guess they concluded the API breakage would be too severe. I assume Java and Win32/DotNet decided the same. Finally, you can Google for old mailing list discussions about QString using UTF-16. Many before have asked "can we just change to UTF-8?".