The amount of variability of a cement from each source and the effect such variations have on the performance for a concrete are subjects that have received considerable attention over the years. As an example, we know there must be a relationship between cement strengths as measured by standard mortar cubes and those obtained in concrete. Yet unless the magnitude of the variation is quite large, the correlation between cube and concrete strengths is rather poor. In fact several long-range studies under closely controlled laboratory conditions indicate that, with cement from a single source, as the cube strengths increase, the concrete strengths sometimes drop. This may be attributed in part to the lack of precision of the respective test methods but there is also some evidence that the chemical reactions of a cement in concrete may differ form its reactions in mortar. What can a concrete producer realistically expect from cement suppliers in the way of technical information that will enable him to produce quality concrete? The following suggestions should help to establish better rapport with cement suppliers and make it clear just what the concrete producer expects: (1) develop a relationship of mutual respect with your suppliers by treating technical information as confidential. (2) ask your suppliers to furnish all pertinent technical information necessary for you to make sound decisions with respect to quality control. And (3) maintain a good working relationship with your suppliers so that you can be confident they will advise you of any deviations form agreed upon standards of uniformity and strength levels. There is a pressing need not only for better communication between consumer and supplier but for a better working relationship between the various segments of the industry. For a number of years there has been a successful cooperative program working in California. Both the northern and southern parts of the state have cement industry technical committees that meet periodically with their counterparts in the ready mixed concrete and aggregates industries. In addition to their function of improving technical communications within the industry, these groups have been effective in working with federal, state, and local government agencies and engineering societies.