The question concerning the necessity of this paper must arise since, we frequently read, systems science is recognised as "coming together" merely 40 to 50 years ago. We contend that (a) this view can be fundamentally challenged (implicitly dealt with in this paper), and (b) that which-ever view is taken, the message of Carr (1964), from his Trevelyan lectures at Cambridge, more than justifies our efforts, that is, "… that history is a dialogue between past and present … between the events of the past and progressively emerging future ends". Thus the history of systems science and the emerging new trends are part of the same dialogue, and so our studies in Liberating Systems Theory (Flood, 1989) are complemented by our historical interests.