This article highlights some original block copolymer properties that have been studied in recent years at the Physico-Chemistry group at the LCPO, giving our view on the physics of block copolymers in solutions (disordered state and self-assembly) and in the bulk (nano-organized films). In particular, we show that beyond the classical results on flexible-flexible block copolymer chains, the architecture (rigidity of the blocks, cyclization, etc) as well as external parameters (temperature, pH, ionic strength) play an important role in the different phases of a material made from block copolymers with controlled architectures. The properties of the various block copolymer systems investigated, in aqueous or organic media, are discussed in terms of free block copolymer chains, self-assemblies and nano-structured/nano-organized films with the aid of techniques such as scattering (light, X-rays, neutrons) and imaging (AFM, TEM).