Labelling theorists use interactionist concepts like the definition of the situation, the looking glass self, and career to study areas like education, health, and crime. The definition of the situation refers to how people's behavior is shaped by how others label them, regardless of their actual behavior. The looking glass self describes how people develop their self-concept through internalizing how others see them. Career in labelling theory refers to how people progress through different statuses based on their labels, such as becoming a "mental patient" through being labeled by a psychiatrist.