The 15 N(p, γ ) 16 O reaction provides a path from the CN cycle to the CNO bi-cycle and CNO tri-cycle. The measured astrophysical factor for this reaction is dominated by resonant capture through two strong 16 O reaction. The results indicate that the direct capture contribution was previously overestimated. We find the astrophysical factor to be S(0) = 36.0 ± 6.0 keV b, which is about a factor of 2 lower than the presently accepted value. We conclude that for every 2200 ± 300 cycles of the main CN cycle one CN catalyst is lost due to this reaction.