So far, the quality of learning strategies has been considered primarily within the framework of the “description paradigm” by investigating the relationship between the use frequency of macrostrategies and achievement. The ADEQUA study is approaching the quality of learning strategic actions in a more finely grained fashion by rating the adequacy of discrete learning strategies at the microanalytical level. Specifically, the study scrutinizes the strategies used by secondary-level students of English as a foreign language while reading an English text in a self-regulated, cooperative learning environment. The strategies they used in overcoming comprehension difficulties were identified and rated on the basis of the students’ videotaped task performance as well as a stimulated recall procedure. In regression models, the adequacy of strategic actions is of major predictive power with considerable effect sizes for students’ achievement. The hypothesis-testing approach adopted here (i.e., to assess the adequacy of every discrete strategy used by means of highly inferential ratings), appears to be promising.