We describe six different tests used to obtain a consistent set of viscoelastic properties for yogurt. Prior to yield, the shear modulus μ and viscosity η are measured nondestructively using the speed and damping of elastic waves. Although new to foodstuffs, this technique has been applied to diverse materials from metals to the earth’s crust. The resultant shear modulus agrees withμ∼E/3for incompressible materials, where the Young’s modulusEis obtained from a stress–strain curve in compression. The tensile yield stressτois measured in compression and tension, with good agreement. The conventional vane and cone/plate rheometers measured a shear stress yieldτos∼τo/3,as expected theoretically, but the inferred “apparent” viscosity from the cone/plate rheometer is much larger than the wave measurement due to the finite yield(τos≠0).Finally, we inverted an open container of yogurt for106 s≫η/μand observed no motion. This demonstrates unequivocally that yogurt possesses a finite yield stress rather than a large viscosity. We present a constitutive model with a pre-yield viscosity to describe the damping of the elastic waves and use a simulation code to describe yielding in complex geometry.