  Along the design process of interactive system many intermediate artefacts
(such as user interface prototypes, task models describing user work and
activities, dialog models specifying system behavior, interaction models
describing user interactions {\ldots}) are created, tested, revised and
improved until the development team produces a validated version of the
full-fledged system. Indeed, to build interactive systems there is a need to
use multiple artefacts/models (as they provide a complementary view). However,
relevant information for describing the design solution and/or supporting
design decisions (such as rational about the design, decisions made,
recommendations, etc.) is not explicitly capturable in the models/artefacts,
hence the need for annotations. Multi-artefacts approaches usually argue that a
given information should only be present in one artefact to avoid duplication
and increase maintainability of the artefacts. Nonetheless, annotations created
on one artefact are usually relevant to other artefacts/models. So that, there
is a need for tools and techniques to coordinate annotations across
artefacts/models which is the contribution of the present work. In this paper,
we propose a model-based approach that was conceived to handle annotations in a
systematic way along the development process of interactive systems. As part of
the solution, we propose an annotation model built upon the W3C's Web
Annotation Data Model. The feasibility of the approach is demonstrated by means
of a tool suite featuring a plugin, which has been deployed and tested over the
multi-artefacts. The overall approach is illustrated on the design of an
interactive cockpit application performing two design iterations. The
contribution brings two main benefits for interactive systems engineering: i)
it presents a generic pattern for integrating information in multiple usually
heterogenous artefacts throughout the design process of interactive systems;
and ii) it highlights the need for tools helping to rationalize and to document
the various artefacts and the related decisions made during interactive systems
design. CCS CONCEPTS $\bullet$ Human-centered computing $\bullet$ Human
computer interaction (HCI)
