The use of the electronic piezocone penetrometer (PCPT) as a potential insitu testing device to evaluate engineering soil parameters is gaining wide acceptance. Improvements in the design of this device have made it possible to measure simultaneously pore water pressure, cone resistance and sleeve friction. However, interpretation of piezocone (PCPT) data is often complex as it is influenced by a number of variables related to the design of the cone, testing procedures and soil characteristics. No standards have been accepted regarding the pore pressure element size and location, which has a significant effect on the magnitude of the measured pore pressures. This research program is a comprehensive experimental investigation using homogeneous and reproducible soil specimens instrumented to monitor the spatial distribution of pore water pressure. Piezocone penetration tests are performed under strictly controlled boundary conditions in a clay calibration chamber system. The objectives are: 1) To conduct very comprehensive and detailed parametric studies to expand the currently available limited data base of piezocone penetration tests in clay, 2) compare existing theories and interpretation procedures to assess their relative merits and demerits, and 3) to compare the results with available field data. The aim is to resolve the complexities currently met during the interpretation of piezocone test data and to assist in the verification of future proposed theories.