Paranoid personality disorder is a common form of paranoid pathology which has been neglected in the research literature. The present manuscript reports three studies on paranoid personality (PP). In Study One, reliable and valid questionnaires from the literature were matched to the DSM-III criteria for PP and administered to 170 college students. Subjects scoring high (1.5 SD above M, or low (1.5 SD below M) on the screening battery comprised the PP group and the comparison group (CG), respectively. These groups were subsequently assessed on paranoid thoughts and paranoid experiences. The results indicated that PPs reported having significantly more paranoid thoughts and paranoid experiences compared to CG subjects. Study Two was an exact replication of Study One using PP, CG, and clinically diagnosed PP (CD) subjects. The findings of Study One were reproduced. Additionally, PP and CD subjects differed significantly from CG subjects on paranoid thoughts and paranoid experiences but the PP and CD groups did not differ from each other. Study Three assessed the willingness of PP subjects to participate in psychological research. PPs were shown to have a lower rate of prior research participation and a higher rate of refusing to participate in future research compared to CG subjects. The results of these studies provide a useful basis for which research on PP can now proceed.