  This paper focuses on the use of knowledge possessed by designers. Data
collection was based on observations (by the cognitive ergonomics researcher)
and simultaneous verbalisations (by the designers) in empirical studies
conducted in the context of industrial design projects. The contribution of
this research is typical of cognitive ergonomics, in that it provides data on
actual activities implemented by designers in their actual work situation
(rather than on prescribed and/or idealised processes and methods). Data
presented concern global strategies (the way in which designers actually
organise their activity) and local strategies (reuse in design). Results from
cognitive ergonomics and other research that challenges the way in which people
are supposed to work with existing systems are generally not received warmly.
Abundant corroboration of such results is required before industry may consider
taking them into account. The opportunistic organisation of design activity is
taken here as an example of this reluctance. The results concerning this aspect
of design have been verified repeatedly, but only prototypes and experimental
systems implementing some of the requirements formulated on their basis, are
under development.
