This article reports on a comparison of lexical items in the vocabulary of Icelandic and Danish sign languages prompted by anecdotal reports of similarity and historical records detailing close contact between the two communities. Drawing on previous studies, including Bickford (2005), McKee and Kennedy (1998, 2000a, 2000b) and Parkhurst and Parkhurst (2001), the authors elicited signs via a word list adapted from Swadesh (1955) and modified by Woodward (1978, 1991) for the purpose of researching sign languages. The signs for 292 lexical items were analyzed by comparing the parameters of hand configuration (together with hand/palm orientation), location, and movement and classified as identical, similar, or different. The results reveal a high percentage of similarity. A much higher degree of lexical similarity appears in the realization of country names than in any other semantic category. The study contributes to work in the field of Nordic sign languages and has methodological implications for the study of sign language vocabulary internationally. Limitations of the study are noted. (Contains 8 tables and 1 figure.)