The last decade has seen an increase in investigations of the psycholinguistic and production attributes of sign and the features of sign which influence learning and memory. However, these investigations usually have not adequately delineated between the learning of individual signs as opposed to the learning of sign lexicons or sign strings and have not discussed features which might differentially influence the learning and recall of single signs and sign lexicons. The current paper reviews existing literature in the area of sign learning and identifies psycholinguistic, psychological, and production features which may influence learning and recall of individual signs as well as sign lexicons. Included in the discussion of features which are hypothesized to influence the learning of individual signs are sign translucency (rather than sign iconicity) and referential concreteness of the sign gloss. Varibles hypothesized to influence sign lexicon learning are cheremic similarity, acoustical confusion, and their relationship to proactive and retroactive interference. Implications of the effects of these variables on the learning of individual signs and on the learning of sign lexicons are discussed.