Developmental idealism (DI) contains a set of beliefs endorsing development, low fertility, and late marriage and causal connections between development, fertility, and marriage. In this paper, we investigate to what extent DI beliefs about connections of economic development with marriage and childbearing are widespread in Turkey. We also compare the views of people concerning these linkages generally with their views of the linkages in their own country. We also investigate whether such factors as regional location, ethnicity, secularism, education, gender, age, marital status, and number of children influence the acceptance of DI beliefs concerning marriage and fertility in Turkey. We present new data from a national survey of urban Turks conducted in 2014. Our analyses reveal substantial evidence that the ideas of DI have been circulated widely among ordinary people in Turkey. Our results also indicate that Turkish people make little distinction between DI as it relates to their own country and DI as it relates to more general or abstract considerations. Moreover, our analyses suggest that region of residence, age, education, gender, marital status, and fertility were related in substantial and statistically significant ways to DI beliefs. However, for such factors as education, gender, marital status, and fertility, we found that the estimated effects were in a different direction from our theoretical predictions. We argue that these findings are important contributions to DI research and that our study raises significant new questions that deserve further research.