This paper aims at removing certain sources of confusion in plasma theory by deriving a complete set of macroscopic equations based on the ionic theory. Relativistic and quantum effects are usually neglected, and an approximation equivalent to that of the macroscopic theory of irreversible processes is adopted. But there is no other approximation, and in particular multiple interactions are fully accounted for. The theory of the dielectric constant and permeability of plasmas is sketched, and there follows an ionic derivation of the equations of continuity, and of energy and momentum transport, based on an exact separation of the long‐range and short‐range forces. It is shown how the short‐range forces contribute to the pressure, the energy flux, and the flux of entropy. The ionic basis of the theory of irreversible processes is discussed, and its relevance to the generalization of Ohm's law. In an appendix, the formal statistical thermodynamics of plasmas is developed in a way which avoids certain difficulties associated with the long‐range interactions.