THE APPLICATION OF STATISTICAL CONSIDERATIONS to the sampling and testing of concrete and concrete-making materials has been addressed by chapters in each of the four previous editions of ASTM STP 169. The first edition, published in 1956, contained the chapter entitled “Size and Number of Samples and Statistical Considerations in Sampling,” by W. A. Cordon. The second edition, published in 1966, contained the chapter entitled “Evaluation of Data,” by J. F. McLaughlin and S. J. Hanna. The second edition also contained the chapter by W. A. Cordon that first appeared in the 1956 edition. The third edition, published in 1978, contained the chapter entitled “Statistical Considerations in Sampling and Testing,” by H. T. Arni. The fourth edition, published in 1994, contained the chapter entitled “Statistical Considerations in Sampling and Testing,” by the author of this chapter. The contributions of previous authors regarding the practical application of statistical probability to the field of concrete and concrete-making materials are hereby acknowledged. This edition will review and update topics as addressed by the previous authors, introduce new clarification of the concepts presented, and include appropriate references.