Given that STEM professionals must regularly engage in transnational and cross-cultural communication, learning to write in their academic disciplines and professions means learning to navigate World Englishes, employ diverse sociolinguistic and rhetorical resources, and negotiate meaning across linguistic and sociocultural borders. Analyzing interviews conducted by using a Grounded Theory method among engineering faculty members and their graduate students at a large public university in the US, this article first discusses a few stated beliefs about language and writing that don't reflect realities about communication in the STEM fields. Drawing on the participants' description of teaching/learning and communication practices in follow-up interviews, the article then offers recommendations to promote the acceptance of complexity and rhetoricity of scientific communication in place of dominant perception that the sciences only use a transparent and universal code of standard English. Further, it recommends specific ways for writing scholars to shift focus from ideology to practice, arguing that doing so can aid research, program, and pedagogy of writing in the disciplines (WID) and writing across the curriculum (WAC), thereby helping promote cross-cultural and transnational communication skills in the STEM fields.