Relatively few Catholic couples in the United States use modern methods of natural family planning (NFP). So too, few Catholic physicians and health professionals prescribe the use of NFP methods for their patients. Reasons for low use of NFP methods include their perceived low efficacy; the complexity of learning, using, and teaching these methods; and the prolonged (and often unnecessary) required abstinence. Newer and simplified methods of NFP have been developed by physicians and scientists that are less complex and use modern technologies of detecting fertility and communicating instructions. Catholic physicians and scientists need to continue to answer the call by the Holy Fathers (from Pius XII to Benedict XVI) to develop secure and scientifically sound methods of NFP.