We propose in this paper a novel approach for human activity follow-up that draws on a distinction between domain-dependent and observer-dependent viewpoints. While the domain-dependent (or intrinsic) viewpoint calls for the follow-up and interpretation of human activity per se, the observer-dependent (or extrinsic) viewpoint calls for a more subjective approach, which may involve an evaluative dimension, regarding the human activity or the interpretation process itself. Of interest are the mutual dependencies that tie both processes over time: the observer viewpoint is known to shape domain-dependent interpretation, while domain-dependent interpretation is core to the evolution of the observer viewpoint. We make a case for using a normative multi-agent approach to design monitoring systems articulating both viewpoints. We illustrate the proposed approach potential by examples from daily life scenarios.