An operational model of context is particularly important for the successful integration of new technical artefacts into complex processes. One of the challenges for ambient intelligence is to embed technical artefacts into human work processes in such a way that they support the sense making processes of human actors instead of placing new burdens upon them. This paper examines some of the strengths and current limitations of a systemic functional model of context. We propose that the dimensions that are relevant to modeling are those that have the most consequences for meaning. This is explored in a hypothetical hospital scenario.