(1) Demands on accuracy, calibration and corrections to be applied in piezocone tests in soft clay, with comments on the test procedures; (2) Piezocone equipments used in the present investigation; (3) Testing programme in the present investigation; (4) Related investigations in Norway and England; (5) Test procedures and related observations; (6) Swedish test fields and principal test results; (7) General behaviour of clays; (8) Development of tip resistance, sleeve friction and pore pressures around a penetrating cone; (9) Evaluation of soil properties in clays; (10) Excess pore pressure dissipation tests; (11) Soil classification