The aim of the Bologna Process is to make higher education systems across Europe more transparent. It is crucial for this purpose that confusion concerning the characteristics of the systems should be replaced by conformity. But, as we will show, conformity brought about at one level may create confusion at another. The curricular aspect of the Bologna Process focuses on a shift to outcome-based and student-centred programmes. Syllabi should now be based on intended learning outcomes (ILOs) and should be adjusted to general level descriptors for qualifications. However, the Bologna documents give no explicit recommendations about the use of grading scales. In Denmark, Norway and Sweden, the reforms of higher education induced by the Bologna process included a change of grading scales and referred to the European Credit Transfer and Accumulation System (ECTS). Through these three case studies, we describe and analyse the political process and argumentation underpinning the decisions to change the grading scales in each country. This includes the problems, both experienced and perceived, with the old grading scales, the various national assessment traditions and the new grading scales. The purpose of the change was not the same in each country, but the ongoing adaptation to a seven-step grading scale was thought to ease the international recognition of the national grades, making mobility easier. Though a seven-step grading scale was implemented in both Danish and Norwegian higher education and also by an increasing number of Swedish higher education institutions, the translation of grades only works on a superficial level. The grading scales designed are fundamentally different as classification systems; they attach different numerical values to grades with identical labels and they relate differently to norm- and standards-referenced judgements of learning outcomes. The information condensed in similar grades from the three countries cannot be equated. The vision of simple transparency turns out to be an illusion. (Contains 1 figure, 8 tables and 2 notes.)