Research on psychotherapeutic internet interventions started in the late 1990s and since then a considerable number of trials have shown that these interventions are effective in the treatment of depression. There is also no reason to assume that they are less effective than face-to-face treatments. This knowledge can be applied in most major areas of mental health care, including preventive services, primary care, specialized mental health care, and general medical care. Internet services can also be organised outside regular mental health care services because no personal contact with patients is needed. Internet interventions can build directly on the many new technological applications of the internet and mobile technology, through ecological momentary assessment and intervention, serious gaming, avatars and automatic emotion recognition, as well as smartwatches. This overview has made it clear that research in this area is booming and that there are many possibilities for all kinds of innovative interventions and applications.