The quasi-neutral limit is a hydrodynamical limit offering a derivation of a PDE of incompressible fluid from a kinetic PDE . In the specific context of the 2D Vlasov-Poisson equation, the quasi-neutral limit leads to the 2D incompressible Euler equation. The purpose of this talk would be to concentrate on the modulated energy method, as developed by Brenier, in order to rigorously justify this limit. Well-posedness of the underlying equations will be discussed as well. The talk will be mostly expositional in nature, with some indication towards contemporary research themes.