This document discusses modelling rich human-computer interaction. It covers status-event analysis, which analyzes both events (things that happen) and statuses (things that are). It also discusses supporting a rich set of phenomena including different types of events and statuses. The document notes that most notations only support a subset of possible phenomena. It provides examples of different types of events, statuses, behaviours, and their properties. It discusses implications for system design, including timescales and interruptions. It also covers naive psychology concepts like user attention and closure. The document proposes that sensor-based, low intention interaction could support richer contexts and incidental interactions.