The rare Iberian endemic Campanula primulifolia, sometimes treated as a synonym of C. alata, was investigated. Its relationships with the two other species placed in C. sect. Pterophyllum, the disjunct E Mediterranean C. peregrina and the NW African C. alata s.str., were re-assessed. All three taxa, based principally on morphological and distributional evidence, were shown to merit independent specific status; a determination key is provided. Special emphasis was given to the conservation aspect of C. primulifolia in Portugal, where it grows in four widely separated provinces, and in SW Spain. All these small populations are seriously threatened and special protection measures are needed to prevent extinction. Our assessment is that it is Critically Endangered [CR B2 ab (iv,v); C2a (i)]. Nomenclatural and taxonomic errors in earlier publications are rectified.