In Taiwan, an EFL environment where English is commonly studied as an L2 and plays a
significant role in both education and work, the effectiveness of English teachers is frequently
discussed. To improve teaching quality, various data collection approaches are used to examine
English teaching effectiveness in formal educational settings, such as public schools and
colleges, as well as non-formal settings, such as private language institutes. The purposes of
this article are first, to explore what models/methods have been used in Taiwan to evaluate
English teaching effectiveness and to identify variables that have been insufficiently examined,
and second, to give suggestions for their measurement. Finally, an actual case is examined to
illustrate what variables are covered in that particular EFL setting and how the existing
evaluation scheme could be improved.