Publisher Summary This chapter discusses job market signaling. The term market signaling is not exactly a part of the well-defined, technical vocabulary of the economist. The chapter presents a model in which signaling is implicitly defined and explains its usefulness. In most job markets, the employer is not sure of the productive capabilities of an individual at the time he hires him. The fact that it takes time to learn an individual's productive capabilities means that hiring is an investment decision. On the basis of previous experience in the market, the employer has conditional probability assessments over productive capacity with various combinations of signals and indices. This chapter presents an introduction to Spence's more extensive analysis of market signaling.