  Empirical software engineering is concerned with measuring, or estimating,
both the effort put into the software process and the quality of its product.
We defend the idea that measuring process effort and product quality and
establishing a relation between the two cannot be performed without a model of
cognitive and collective activities involved in software design, and without
measurement of these activities. This is the object of our field, i.e.
Cognitive Ergonomics of design. After a brief presentation of its theoretical
and methodological foundations, we will discuss a cognitive approach to design
activities and its potential to provide new directions in ESE. Then we will
present and discuss an illustration of the methodological directions we have
proposed for the analysis and measurement of cognitive activities in the
context of collective software design. The two situations analysed are
technical review meetings, and Request For Comments-like procedures in Open
Source Software design.
