The neutron capture cross section of 237 Np was measured between 0.7 and 500 eV at the CERN n_TOF facility using the 4π BaF 2 Total Absorption Calorimeter. The experimental capture yield was extracted minimizing all the systematic uncertainties and was analyzed together with the most reliable transmission data available using the SAMMY code. The result is a complete set of individual as well as average resonance parameters [D 0 = 0.56(2) eV, γ = 40.9(18) meV, 10 4 S 0 = 0.98(6), R = 9.8 (6) (2002)]. The results indicate that a new evaluation combining the present capture data with reliable transmission data would allow reaching an accuracy better than 4%, in line with the uncertainty requirements of the nuclear data community for the design and operation of current and future nuclear devices.