Modern fertility awareness-based methods (FABMs) of family planning have been offered as alternative methods of family planning. Billings Ovulation Method, the Creighton Model, and the Symptothermal Method are the more widely used FABMs and can be more narrowly defined as natural family planning. The first 2 methods are based on the examination of cervical secretions to assess fertility. The Symptothermal Method combines characteristics of cervical secretions, basal body temperature, and historical cycle data to determine fertility. FABMs also include the more recently developed Standard Days Method and TwoDays Method. All are distinct from the more traditional rhythm and basal body temperature methods alone. Although these older methods are not highly effective, modern FABMs have typical-use unintended pregnancy rates of 1% to 3% in both industrialized and nonindustrialized nations. Studies suggest that in the United States physician knowledge of FABMs is frequently incomplete. We review the available evidence about the effectiveness for preventing unintended pregnancy, prognostic social demographics of users of the methods, and social outcomes related to FABMs, all of which suggest that family physicians can offer modern FABMs as effective means of family planning. We also provide suggestions about useful educational and instructional resources for family physicians and their patients.