We report on the self-aggregation patterns of sodium deoxycholate investigated successively by small-angle neutron scattering, quasi-elastic light scattering, viscosity, electrical conductivity, and time domain reflectometry as a function of pH, temperature, and detergent concentration. Experimental results reveal a rodlike association which seems to be strongly dependent on the pH and ionic strength. The radius and length of such conformations compare reasonably well with the dimensions of helical models and rods previously observed by small-angle X-ray scattering and electronic spin resonance. We also show the existence of two critical micellar concentrations. The lower one, corresponding to small primary micelles, is pH and temperature independent. The second one, which is strongly dependent on pH and temperature, leads to the formation of larger aggregates and in some cases to gelation. A sharp phase transition between solution and gel was observed at pH 7.5. The growth of the aggregate occurs along the rod’s axis and is favored by a decreasing pH. At the opposite, the decrease of the micellar size along the rod’s symmetry axis if favored by an increase of the pH.