The P V T properties of 2,3,3,3-tetrafluoroprop-1-ene (CF(3)CF=CH(2), HFO-1234yf), an environmentally friendly refrigerant, were measured using a constant volume apparatus. Measurements were carried out at temperatures from (243 to 373) K and at pressures from (84 to 3716) kPa. A total of 136 experimental points, taken along 12 isochores, were obtained. Our experimental results were compared with a preliminary equation of state. The measurements were also regressed to the Martin-Hou equation of state. No other data on this fluid were found in the literature for the superheated region.