Progress toward elimination of onchocerciasis, or river blindness, is the result of decades of dedication to controlling this disease. Over the past few years, mass drug administration of ivermectin has moved the goal from control to elimination. As programs work toward this, they need appropriate diagnostic tools to identify exposure to Onchocerca volvulus (Ov) to detect possible recrudescence. PATH and its partners have developed a rapid diagnostic test (RDT) that detects immunoglobulin G4-related disaease (IgG4) antibodies specific to Ov16 and it will be manufactured by Standard Diagnostics, Inc. (SD). Prior to availability, its performance was evaluated in a series of assessments in both lab and field settings.