Measurements of total croes sections for 3He(3He,2p)4He have been made for center-of-mo-mentum energies between 80 keV and 1.1 MeV. A continuously recirculating differentially pumped gas target system was employed to minimize uncertainties in energy loss and straggling. A cal ori metric device was used to integrate the beam current within the target gas. Proton angular distributions were measured at seven energies. The measured cross-section factor, S(E), was fitted to a linear function of energy for E c.m. < 500 keV: