We don't formally evaluate the skills of translators before registering at Babelcube. However, we are constantly creating ways to increase a rights holder's (publisher's or author's) confidence in a translation's quality. For example, a right holder can ask the translators to work as a team on a book translator - a) a main translator and b) an editor and proofreader. Also, translators who have worked on other Babelcube books often have reviews written by other Babelcube rights holders on their Babelcube profile.