A comparison of the relative costs of the injectable contraceptive (depot medroxyprogesterone acetate) and the hormonal implant (Norplant®) indicates that the implant is a less costly contraceptive option when it is used for its full five-year lifespan. Over a five-year period, the implant costs $107 annually, compared with $140 per year for the injectable. However, if a woman discontinues the implant before she has used it for at least four years, the injectable becomes the less costly option. Relatively high continuation rates--around 95% annually--are necessary to make the implant the more cost-effective contraceptive method.