Volumetrics describe the relationship between the mass of matter and the volume it occupies. Density, a quotient of mass to volume, is the most commonly used parameter for HMA mix design, quality assurance, and quality acceptance. The proper use of density measurements depends strongly upon the ability to accurately and precisely measure both the desired volume and mass of the mixture. Three independent studies were conducted to investigate the variability of density measurements (i.e., various measurements of bulk specific gravities), control of volumetric proportions during construction, and the influence of in-place densities on pavement performance.