Information Technology (IT) plays an increasingly important role, both for individuals, business, and society as a whole. IT systems are artefacts (human made). They are designed for various purposes; for instance to support workflow, to compute, to communicate, to deliver services, to facilitate learning, or simply to entertain. Research within several academic disciplines has resulted in a variety of quality ideals which may guide designers and evaluators of IT artefacts in their context of use. However, the matter of how to understand the artefact and its qualities-in-use is often implicit in Information Systems research. This thesis proposes a way of conceptualizing the IT artefact based on theoretical a framework primarily built on semiotics (the study of signs) and socio-instrumental pragmatism (focusing IT as an instrument in social action). Further, the results include concepts for understanding IS use qualities in a socio-instrumental context. The results are formulated as practical theory, which means that the concepts at hand are readily applicable and useful in practical work with IT design and IT evaluation. The research process consists of a number of cycles, alternating between theoretically informed conceptual development and evaluations of IT artefacts in heterogeneous contexts of use. The research design is based on American pragmatism and inquiry as a theory of knowledge.