This article discusses the development of a protocol for testing and removing arsenic pesticide residues from textiles. This research was conducted by a team at the Arizona State Museum Conservation Laboratory and with funding from a National Center for Preservation Training and Technology (NCPTT) grant that partially supported the purchase of equipment, supplies, and a stipend for a graduate student assistant. A procedure for the survey of toxic metal pesticides on textiles and a methodology for a treatment to remove arsenic-based pesticides from textiles were created. The project included the following activities. Scholars of Navajo (Dinè) textiles and Navajo weavers were consulted as the project was developed. The entire collection of Navajo textiles was surveyed with a portable x-ray fluorescence instrument (pXRF). A protocol for the testing procedure was developed to make this task both (1) efficient in sometimes difficult storage access conditions and (2) useful for the development of an arsenic removal method. A protocol for arsenic removal was based on testing of a series of arsenic-treated samples (doses based on typical amounts found during the survey on ASM collections). The samples were pXRF tested before and after variations in washing technique including time, temperature, pH, and agitation. Wash water from the samples was also tested for arsenic. Three museum textiles were successfully cleaned of arsenic pesticide residues.