The difficulty to treat a chronic total occlusion (CTO) had been the Achilles' heel of percutaneous coronary intervention (PCI), and that is why in a classic editorial, Bernhard Meier had termed the chronic occlusion a “different animal”. Thirty years later, the revascularization of CTOs has made huge progress with introduction of new techniques and strategies. However, there remain some subsets of CTOs that present a particular challenge to the operator, such as the severely calcified occlusion or the ostial occlusion. In this edition of the journal, Guelker et al. present their experience with ostial CTO as compared to non-ostial CTO. They observed an about 12% lower success rate with longer procedure and radiation duration for ostial as compared to non-ostial CTOs. A similar analysis had been presented from a multicentre data base, but, with the conclusion that the success rates were not affected. But when the success rates of these two studies are compared, they are both below 85%, which is less than what we would expect among the very experienced operators of today, where rates are regularly in the range of % to 95%. This underscores that ostial occlusions require a specifically skilled operator.