ILUMIEN I study has reported complementary use of intracoronary physiology (fractional flow reserve: FFR) and imaging (optical coherence tomography: OCT) by the findings that OCT may change PCI strategy even if the indication or end-point was decided by FFR, although there are many discussions debating which modality would be better for PCI guidance or diagnosing coronary artery disease between intracoronary physiology and imaging. Furthermore, DEFINE-FLARE and SWEEDE-HEART studies has demonstrated non-inferiority of instantaneous wave free ration (iFR) to FFR as PCI guidance, and the usefulness of FFR calculated using multidetector computed tomography (FFRCT) and that obtained by three-dimensional coronary angiography (QFR) have been demonstrated recently. These newly developed physiological indexes may change the patients’ flow in daily clinical practice. Thus, complementary use of intracoronary physiology and imaging would be discussed in this session based on these recent data.