Interrelationships between the flat dilatometer readings (lift-off pressure, p0, and expansion pressure, p1) and piezocone readings (cone tip stress, qt, and penetration porewater pressures, u2) are explored for three soft clay sites. Within the intact regions, the p0 and u2 measurements are quite consistently similar in magnitude, whereas qt is variably larger than both p0 and p1, perhaps somewhat dependent on the effective friction angle of the clay. Companion sets of DMT and CPTU at a given site could be used to better define the extent of the crustal zone, degree of fissuring, intact regions, and related permeability characteristics of these substrata within a clay formation.