The LR-18 RIL was developed from a cross by CDC Robin, a small red cultivar released in 1999, and 964a-46, a large green breeding line from the lentil breeding program at the Crop Development Centre (CDC), University of Saskatchewan. LR-18 individuals were genotyped with the Lc1536 GoldenGate OPA and almost one third (484) of the loci were polymorphic and could be used for mapping purposes. Additionally, LR-18 individuals were screened with six SSRs from Hamwieh et al. resulting in additional data utilized in the mapping process. The map has seven linkage groups that likely represent the seven chromosomes in lentil. The linkage groups range from 58 cM to 226 cM and together they cover 834.7 cM.