This study investigated: (1) what secondary school teachers, who participated in academic mathematics studies, learned about the connection between mathematics and other fields, and how this knowledge contributed to their teaching; and (2) what athematicians, who taught in that program, wanted to teach teachers about this connection. Data sources included interviews with five research mathematicians and 14 teachers. Analysis revealed that the mathematicians wished to teach teachers about the mutual contribution between mathematics and other fields. Yet, the teachers reported on enriching their knowledge only about the contribution of mathematics to other fields but not about the contribution of different fields to the development of mathematics. Interpretations and ways to address this discrepancy are proposed in relation to two areas: mathematical applications and modeling, and the history of mathematics.