Methods of treating dilute plasmas were studied. Emphasis was placed on fundamental rather than semi-empirical methods. The analysis is essentially a detailed account of the Prigogine school's approach to non-equilibrium statistical mechanics. The starting point is the Liouville equation describing the motion of the entire system. The advantage of using the Liouville equation is that it is linear as contrasted to the non-linear equations of dynamics. The Liouville equation is solved (initial value problem) formally by means of the resolvent expansion technique. Terms in the expansion are associated with diagrams, which are then used to study properties of the terms. Classes of diagrams which are relevant to physical situations can in some cases be summed and lead to macroscopic equations of transport. The procedure is illustrated for weakly interacting systems.