Resumen
We report on a care setting where staff looking after ex-psychiatric hospital patients used mobile and stationary communications technology (e.g. mobile phones and a messaging system) and physical artefacts (e.g. whiteboards and Post-It notes). Building on previous ethnographic investigations, we show that the concept of trajectory (or an ongoing course of action) was important when generating a particular understanding of staff?s care work. We argue that sensitivity to this concept and related subconcepts was helpful in identifying the key transitions, cycles, plans and management issues in staff?s ongoing work. We present verified trajectory-informed scenarios and themes emerging from fieldwork and show that the snapshots of work described in the scenarios were useful for establishing current and future interactional needs among staff and residents. We also show how trajectory helped ground a design for a situated display. Finally, we describe the strengths and benefits of trajectory as ?a way of looking? in fieldwork aimed at socio-technical system design in settings where supporting collective, ongoing, contingent care is important.