Mental disorders are disabling and common. Depression, for example, has greater global burden of disease than any physical disorder, and almost a third of people will experience some form of mental disorder in their lifetime. The effectiveness of psychological interventions is well established. Cognitive Behavioral Therapy is particularly effective for mood and anxiety disorders. But CBT is demanding of time and resources, partly explaining its limited availability, even in public systems. More and more people have access to the Internet and smartphones, even in the developing world. Internet therapies (including smart-phone apps) have been developed, offering CBT. Can technology help with access to CBT? In this chapter, we will look at the effectiveness of iCBT for several illnesses, based on new evidence from recent randomized controlled trials and meta-analyses, noting that while there is evidence for this therapy, not all programs have the same results. We consider iCBT in the real world, by looking at some popular apps and websites, including MoodGYM, and also present a case from The Scarborough Hospital (where we implemented a free-at-the-point-ofuse iCBT program), demonstrating how it can be applied in an outpatient setting. We also present the current strengths and limitations associated with iCBT. Finally, we consider future directions for this field, considering chatbots and the possibilities with Artificial Intelligence.