A statistical treatment of the complex morphology of polymeric chains, trees and networks is developed. Its usefulness consists in the possibility to describe intricate properties in terms of a twofold diagram and a very simple correlation function. The method proposed here has been applied in other fields such as: (i) porous media,1-5 (ii) physical adsorption,6-7 and (iii) the morphology of products of aggregation and gelation.8 Firstly, having in mind that the span of applications is very wide, the foundations of the twofold description are stated in a rather abstract form. Subsequently, they are exemplified in some detail for the case of statistical copolymer chains. Finally, a great variety of systems of interest in polymer science in which twofold description is valuable are briefly pointed out.