This chapter reviews literature suggesting the benefit of integrating new conceptions of workplace interest with research on the development of interest that has primarily been studied in educational contexts. It discusses the implications of the Four Phase Model of Interest Development for considering how vocational interest might be supported to develop and/or deepen. The four-phase model describes interest as developing through phases regardless of age, or whether the context of its development is in the home, in or out of school, or in the workplace. Interest is considered to be content specific by both those studying interest in terms of the four-phase model and those studying vocational interest. Although the fourth and fifth characteristics have not been a focus of research on vocational interest, they are relevant to the workplace. The case of the engineer illustrates that employers and the workplace can support the development of interest, and also that they may contribute to the decline of interest.