This chapter will examine the obsessive fear that a person may commit an act they do not wish to do. This includes people who have images of themselves performing violent acts, people who worry that they may shout out something inappropriate or detrimental, as well as a variety of other behaviours. One example of a very distressing type of obsession is people who have images of themselves harming others by knocking people over in the road or even starting to wonder if they have committed an awful crime which they may have heard about via the media. People with this type of obsessive thoughts have been known to ‘confess’ to the police and in severe cases may be arrested for wasting police time.

The idea of ‘thought-action fusion’ is the idea that having a thought is as bad as performing the act or that thinking of an event makes it more likely to happen.

Fear of shouting out something inappropriate or obscene is also discussed and the distinction between this and Tourette syndrome.

Taboo obsessions involving fear of paedophilia are often in this category but because of the extreme distress and misunderstanding these obsessions can cause, they will be discussed in a separate chapter.