This volume contains contributions from cooperative research activities in physics and chemistry and addresses heterogeneous systems like atoms and molecules in complex environments, dye molecules like the retinal chromophore in the protein box of the human eye, interacting atoms/molecules in the interlayer of adsorbed structures, nucleation and domain formation processes in magnetic and martensitic systems. The particular aim of the contributions is to deduce the connection between different grades of heterogeneity and to bridge the gap between chemicals and heterogeneity on the atomic scale, and the physics of macroscopically heterogeneous systems. Besides the diverse experimental tools employed in the investigations, accompanying theoretical investigations range from ab initio molecular dynamics studies of the microscopic systems to Monte-Carlo simulations of the larger-scale problems.