In recent years, the percentage of patients with multivessel disease and multiple complex stenoses have significantly increased. One factor contributing to this increase is the proportion of elderly and very elderly patients who have been turned down by the Heart Team for surgical revascularization (Landes et al. in Catheter Cardiovasc Interv, https://doi.org/10.1002/ccd.27375 , 2017; Waldo et al. in Circulation 130:2295-2301, https://doi.org/10.1161/CIRCULATIONAHA.114.011541 , 2014). In addition, the marked increase in patients with significant comorbidities further contributes to the increase in patients referred to the interventional cardiologist for stenting procedures. Mostly, the complexity of these patients is characterized not only by their comorbidities but also by multivessel disease, bifurcation disease, left main disease, or stenoses of calcified or tortuous vessels, degenerated saphenous vein graft lesions, and thrombotic lesions (Kirtane et al. in Circulation 134:422-431, 2016; Gennaro Giustino et al. in JACC 86:1851-1864, 2016) These specific lesion types are typically associated with lower rates of procedural success and higher rates of recurrence or major adverse cardiac events (Kirtane et al. 2016) Coming along with this problem, virtually no study exists evaluating revascularization strategies, i.e. percutaneous coronary intervention (PCI), coronary artery bypass graft surgery, or medical therapy alone in complex patients with complex coronary anatomy. Therefore, we are confronted with an increasing patient population that is understudied and potentially underserved. In the absence of robust, accurate, objective, and consistent evidence which could help us in decision-making (e.g. best revascularization strategy, complication prevention, post-interventional medical therapy), we have to stick to personal experience and patients' preferences. In this article, we provide an overview about common definition of complex PCI, general strategies to help decision-making in these patients, and give an overview about post-interventional medical treatment.