We present here a groupware (MEMO-Net) based on a model (DIPA), which uses and simplifies the concepts of Problem-Solving methods. This model comes from a review of Design Rationale formalisms that gave rise to the ABRICo formalism. MEMO-Net enables exchange structuring in order to improve dialog quality and reusability. MEMO-Net prefigures a new KM approach, named “cooperative KM” where we propose virtual work environments for groups that will consist in new “coordination mechanisms”.