Two sessions at the ACI 2008 Spring Convention will pay tribute to 13 landmark papers in concrete materials research and recognize the importance of materials innovations to the concrete community. The papers will be presented by noted experts that will describe each paper and its impact on the concrete community. A special publication associated with the sessions will be published, presenting each landmark paper in its original form along with a foreword from each presenter. "Proportioning Concrete Mixtures" by Duff A. Abrams is presented here with an abbreviated version of V.M. Malhotra’s foreword.