Whether they are implicitly or explicitly defined the requirements
for the system need to be familiar to the people participating
in the group.
The ideal group size for a CRC card session is five or six people.
This size generally allows everyone to productively participate.
In groups of larger size productivity is cut by more disagreements and
the amount of participation by each is lower.
If there are more than six people, one solution is to have the extra
people be present strictly as observers.
The group five or six people in the core group should be composed of
developers, domain experts, and an object-oriented