Abstract – The evolution of natural ecosystems is controled by a high level of biodiversity, In sharp contrast, intensive agricultural systems
involve monocultures associated with high input of chemical fertilisers and pesticides. Intensive agricultural systems have clearly negative
impacts on soil and water quality and on biodiversity conservation. Alternatively, cropping systems based on carefully designed species mixtures
reveal many potential advantages under various conditions, both in temperate and tropical agriculture. This article reviews those potential
advantages by addressing the reasons for mixing plant species; the concepts and tools required for understanding and designing cropping
systems with mixed species; and the ways of simulating multispecies cropping systems with models. Multispecies systems are diverse and may
include annual and perennial crops on a gradient of complexity from 2 to n species. A literature survey shows potential advantages such as
(1) higher overall productivity, (2) better control of pests and diseases, (3) enhanced ecological services and (4) greater economic profitability.
Agronomic and ecological conceptual frameworks are examined for a clearer understanding of cropping systems, including the concepts of
competition and facilitation, above- and belowground interactions and the types of biological interactions between species that enable better
pest management in the system. After a review of existing models, future directions in modelling plant mixtures are proposed. We conclude on
the need to enhance agricultural research on these multispecies systems, combining both agronomic and ecological concepts and tools