Recent technical advances have set the stage for multi-detector CT as a comprehensive technique for assessment of coronary artery disease. Cardiac CT became a possibility in the mid 1990s, and with the introduction of multi-detector row CT, non-invasive coronary CT angiography (cCTA) is now an established technique for the assessment of coronary heart disease. Further advancements in CT techniques such as increased number of detector arrays and reconstruction algorithms have set the stage for CT to have a role of in the evaluation of myocardial perfusion and viability. However, there are concerns for using CT as a screening and diagnostic tool because of the inherent risk of radiation dose received during cardiac assessment. This prompted further modifications in CT scanners and refinement of scanning techniques to reduce radiation dose received. The work has paid off significantly, and recently published data show that cCTA can be performed with doses as low as 1–2 mSv (1–3). In this issue of Imaging, two excellent reviews discuss the current status of cCTA and myocardial perfusion imaging and their clinical utility and future directions (4,5). cCTA fills the need for a non-invasive alternative to invasive coronary angiography for evaluation of coronary artery disease. The quality of cCTA is also dependent on patient factors such as body weight, age, heart rate and rhythm. The negative predictive value of cCTA is very high, which may obviate the need for an invasive catheter angiography. Despite the high negative predictive value, the concern of radiation, especially in asymptomatic individuals has limited its application widely. Apfaltrer et al. (4) describe the technical evolutions in cCTA and the methods to keep radiation dose minimised without compromising imaging quality. However, the major hurdle lies in the lack of evidence of cost effectiveness and on the patient outcome following a cCTA. Therefore, now the focus is on evaluating and optimising radiation dose reduction techniques, the cost effectiveness and impact of cCTA on patient management and outcomes. Prospective long-term studies comparing traditional diagnostic pathways in coronary artery disease to those incorporating cCTA are lacking, and the effects of cCTA implementation on patient management and outcomes are not well known. Expanding the role of CT beyond cCTA is in characterisation of atherosclerotic plaques, myocardial attenuation deficits and left ventricular wall motion and function. These are promising, but still in investigative stage and needs more clinical validation. MDCT is well suited to evaluate myocardial viability; however, the challenges are similar to cCTA, and when used as a comprehensive imaging study including cCTA, the radiation exposure is substantial, which is currently prohibitive. The high isotropic resolution of MDCT is very useful for studying the perfusion and therefore the interest in this technique by researchers. Magnetic Resonance Imaging (MRI) is the current reference standard for evaluation of myocardial perfusion. MRI has no ionising radiation and provides excellent soft tissue characterisation, which makes it very attractive. However, state of the art MRI scanners may not be available in all places and is contraindicated in patients with pacemakers or defibrillators. In the second review by Marcus et al. (5), the emerging application of CT for myocardial perfusion is described, and overviews of the current competing techniques are nicely outlined. In the past decade, there have been substantial improvements in image acquisition, reconstruction, work flow and analysis of cardiac CT images. The major limitation due to radiation dose is probably abated to a certain extent by the dose reduction strategies. These advances have made cardiac CT a suitable alternative to current techniques; however, clinical experience is limited, and therefore one has to wait for more results from larger clinical trials. Long-term cost-benefit analysis studies are probably the best bet to overcome this challenge and establish the role of cCTA and Cardiac CT imaging in coronary artery disease. None declared.