The wide heterogeneity of conclusions of the studies addressing diversity and performance is well explained by the multi-meaning nature of these notions and their tight connection to the historical and environmental context. The time and culture, the management practices, the professional integration modes, the conjuncture and the inter-organisational context, as well, affect the performance of diversified teams. To make diversity a real performance vector, organisations are committed to conceive and adopt policies which inscribe the change in long-duration (societal perspective), promote integrating-management practices, sensitive to the culture and the identity of individuals (organisational level) and adopt mentoring and leadership practices (individual level).