Design learning in interior architecture relies on the ability to translate cultural meaning, spatial perception, and functional requirements into coherent design solutions. This chapter explores how interior design education can be enriched when cultural knowledge and language use are embedded directly into the design process through applied, project-based learning. The study examines a collaborative design project in which Romanian interior design students developed interior proposals inspired by Mexican domestic culture, supported by interaction with Mexican students engaged in applied English communication. The Romanian students’ design work reflects a clear disciplinary shift while using computer-aided design (CAD) program. Educated primarily within a minimalist European framework, they were challenged to engage with Mexican spatial traditions characterized by expressive color, ornamentation, symbolism, and material richness. As a result, students produced interior design proposals that moved beyond familiar formal strategies toward more culturally responsive and conceptually layered solutions. For the Mexican participants, English functioned as a professional tool rather than an academic subject, as they were required to explain cultural references, spatial practices, and design concepts clearly and precisely to nonspecialist peers. The collaborative project fostered applied learning across both disciplines. Students demonstrated improved design articulation, stronger visual and digital communication skills, and increased awareness of how cultural context shapes interior space. Instructors observed higher levels of engagement, creative risk-taking, and reflective design thinking compared to previous course iterations. The chapter argues that integrating language learning and intercultural dialogue into design practice can strengthen disciplinary learning outcomes and better prepare students for professional contexts where interior design, 3D modeling, communication, and cultural awareness are inseparable.