In a spectacular decision, in 2012 the Czech Constitutional Court declared the Landtová judgment of the CJEU ultra vires and therefore inapplicable on the territory of that Member State. The CJEU’s judgment was rendered following a request for a preliminary ruling by the Czech Supreme Administrative Court. The real and underlying conflict, however, was of an internal nature and took place between two of the highest courts of the Czech Republic well into 2013, making it an illustrative example of how the mechanisms of judicial dialogue actually work in practice. This contribution first looks at both the horizontal and vertical aspects of the so-called Slovak Pension Cases. It further assesses them from the perspective of judicial dialogue in its procedural and substantial features, while finally discerning possible consequences that the ultra vires decision of the Czech Constitutional Court might bring about.