This technical brief was developed by members of the Caucus on New and Underused Reproductive Health Technologies, a thematic group established under the auspices of the Reproductive Health Supplies Coalition. One in a series of ten, this brief focuses on the levonorgestrel intrauterine system (LNG-IUS). It provides a basic description of the LNG-IUS, as well as information on efficacy, current program/sector use, manufacturing, registration, and pricing.