Every day life requires frequent switches between tasks in order to achieve goal-directed behaviour. For example, driving presents us with a complicated environment wherein many sub-tasks (speed monitoring, steering, recollection of directions from memory etc.) must be switched between in order to arrive safely at our destination. However, as working memory is limited in capacity, the question arises as to how a new task is implemented in working memory in the face of conflicting activation from the now-irrelevant task. The mechanisms that allow such fluid switching are measured by utilising the so-called task-switching paradigm. Within this paradigm, participants switch between two or three simple cognitive tasks (e.g. odd/even; higher/lower than 5 judgements on number stimuli). Recent research from the task-switching paradigm has suggested that task performance is afforded by activation of task-relevant representations in working memory. Such an established representation guides behaviour by directing attention to task-relevant stimuli and actions whilst filtering out task-irrelevant information. The present chapter provides a critical review of behavioural results in the task-switching paradigm, outlining the controversies that have surrounded this popular paradigm in recent years. This chapter also reviews the concept of inhibitory mechanisms in task-switching, serving to suppress the activation levels of the previously relevant task.