Studies investigating the written performance of students taught in face-to-face compared to Blended Learning environments have shown that the hybrid group’s performance is either equal to that of the control group taught face-to-face, or that the treatment groups (where Blended Learning is applied) even outperform the control groups. Looking at the introduction of Computer Assisted Language Learning in general and Blended Learning in particular, this paper aims to discuss the abovementioned findings by comparing them to the results of a research project carried out at a university of applied sciences in Graz, Austria. The section regarding the Blended Learning environment notably focuses on the advantages of said design for teaching ESP (English for Specific Purposes). The written performance of students taught face-to-face (control group) and that of students taught in a Blended Learning environment (treatment group) are discussed taking into account the respective theoretical background with regard to assessing writing. To that end, the students’ results in a pre-test at the beginning of the semester and a post-test at the end of the same semester are evaluated and compared. Finally, conclusions pertaining to the students’ performance are drawn and possible links between these results and the relevant method of teaching are established.