A critical element for evaluation of natural family planning (NFP) methods is client autonomy. Autonomy in NFP refers to clients who can identify their fertile days and apply this method without teacher assistance. The results of this study show that clients who are autonomous have a 12-month continuation rate of 96.7% and a pregnancy rate of 1.7% after beginning charting. The non-autonomous clients had a 12-month continuation rate of 34.3% and a pregnancy rate of 24.8% after beginning charting, significantly different from the autonomous clients. Using a bivariate analysis, we found that women 30 years and older who had two children or more, and women in the same age group (30 years and older) who wanted to limit rather than space pregnancy were significantly more likely to become autonomous. These findings have implications for NFP programs and future evaluation efforts.