Purpose: This article aims at presenting a conceptual framework which, theoretically grounded on complexity, provides the basis to conceive of online language courses that intend to respond to the needs of students and society. Design/methodology/approach: This paper is introduced by reflections on distance education and on the paradigmatic view underlying a large component of language courses in Brazil. From these considerations, it is reasoned that the complex paradigm offers a foundation to conceive a unique design concept. The complex educational design is then described in its constructs and features. To conclude, reflections and implications of this original, conceptual model are taken into account. Findings: An online language course design--although aiming at schematizing a series of learning situations and defining target teaching contents--needs to contemplate unpredictability and instability which prevent it from having a pre-established fixed design. Instead, it should be based on an open syllabus, structured according to learning situations that, suggested/selected by students, respond to their interests, and through which linguistic items will be introduced and discussed. Originality/value: This paper presents a conceptual framework which, theoretically grounded on complexity, provides the basis to conceive of online language courses that are responsive to the needs of students and society. While the complex paradigm is emerging and winning followers and complex thinkers over, we have the continuing education segment to open up trial areas and spread out the paradigmatic novelty. The conceptual framework presented and theoretically articulated is now open to be operationalized and interpreted in its potentiality. (Contains 4 figures and 6 notes.)