The evaluation of patients with the complaint of “dizziness” is a frequent occurrence in the ED. It accounts for 3.5–11% of ED visits. The word dizziness is a nonspecific term used by patients and healthcare professionals to describe a disturbed sense of wellbeing, usually perceived as an altered orientation in space. Vertigo is defined as an illusion of movement of oneself or one’s surroundings. It is usually experienced as a sensation of rotation or, less frequently, as undulation, linear displacement (pulsion), or tilt. Although vertigo usually suggests a vestibular disorder that can involve the inner ear or brain, this symptom itself cannot reliably localize the disorder. Dizziness or vertigo can result from numerous disorders of a complex human balance system. Despite the inherent complexities, the ED evaluation of dizziness or vertigo can be simplified by a systematic approach in history-taking, physical examination, and laboratory testing.

It is increasingly recognised that action ascription is not just a matter of inference, but is a form of social action in its own right. This chapter explores two key implications of this finding. First, in treating action ascription as a social action we have formal grounds for the claim that analyses of action ascription must necessarily include inspection of third positioned actions, as ascribing action is an account-able action in its own right. Second, we have procedural grounds for examining the suppression or avoidance of inferences about the action(s) in question by participants. A collection of instances of ‘offers’ that are occasioned or ‘touched off’ by some prior action, and are variously designed to be heard as such, are analysed in the course of this chapter to provide an empirical anchor for these two theoretical claims.