If one dismisses the Prophetess Deborah who in her famous song after the victory over the Philistines sang "The mountains melted before the Lord" and her contemporary (on our time scale), the Egyptian Amenemhet, who designed the water clock, which was in fact the prototype of the capillary viscometer, the beginnings of modern rheology should be linked up with the works of the classics of natural sciences of the 19th century: J ames Clerk Maxwell, Lord Kelvin, and Ludwig Boltzmann, whose names are associated with the origination of the fundamental concepts of rheology. The founda­ tions of experimental rheology were also laid in the nineteenth century in the works of J. M. L. Poiseuille, T. Schwedoff, and others. The next step in the advancement of rheology dates back to the twenties of this century when E. C. Bingham, G. W. Scott-Blair, A. Nadai, and M. Reiner developed the fundamentals of the engineering approach to the technological properties of real materials, thereby outlining the numerous potential applications of rheology. The progress of polymer rheology was especially vigorous after World War II when polymeric materials found their way into industry and the home. Today, rheology is 60-70 per cent concerned with investigations of this kind of materials. Polymer rheology has evolved as an independent science over the last 10-15 years and is in its various aspects intimately entwined with molecular physics, continuum mechanics, and the processing of polymeric materials.