Heterogeneity, diversity, and inclusion dictate the rhythm of a changing society and, thus, demonstrate the challenges educational institutions face. This also applies to teaching English as a foreign language, where teachers are encouraged to meet this challenge with specially tailored learning arrangements. Therefore, Maria Eisenmann not only introduces theories of heterogeneity, differentiation and inclusion, but also presents individualizing methods and learning strategies for the practice of teaching. The author describes methodological options and many innovative incentives for internal differentiation enhancing learner involvement, learner centeredness, and learner autonomy.