Is There a Distinction Between Vertical and Horizontal Direct Effect of Directives?

The direct effect of EU directives was recognised more than 40 years ago. However, directives are not by definition binding for individuals, which is one of the reasons why the CJEU was reluctant to enable to rely on directives in the litigations between private parties. This has created unpleasant difference between horizontal and vertical situation, which has been mitigated by several other doctrines flowing from case-law. Could it be argued that the difference between horizontal and vertical effect of directives does not exist anymore? This contribution will try to state the reasons why it is not the case and the distinction is still present in theory as well as in practice