Teach yourself is a series of language learning courses produced by Hodder & Stoughton. It has courses in all the major languages and also some of the less spoken or ancient ones. It has not only traditional courses but also others for improvement or learning scripts.
Among strenghts of these courses are: systematic approach, explanations of grammar, good quality audio
Weaknesses: The claims of CEFR level goals need to be taken with a grain of salt as more vocabulary and additional resources are usually needed to reach them.
The most used series by HTLAL members are Complete and Perfect Your x courses.
Apart from these, TY produces as well Get Started In x, Speak x With Confidence and Last Minute courses. Each promises to get you to one of the CEFR levels with suspiciously small amount of words and some are more a phrasebook than a course.
TY produces as well reference series: Essential x Vocabulary, Essential x Grammar, Essential x Verbs and books on foreign scripts.
Individual courses reviews:Edit
Claims to get you to B2 level and 2000 words.
Perfect Your courses:Edit
Claims to get you to C1 level and 1000 more words