This chapter includes four diverse applications of the 2TSF model: in production theory, where the model can be used to estimate the effects of management in battle with inefficiency; in primary public education, where we examine whether issues of race, income, but also unobservable heterogeneity, may affect the test scores of pupils; in environmental issues where businesses are socially pressured to operate in a more sustainable way; and in the World Happiness Report, where we apply the 2TSF logic to the data.