Blake instantly realised that Cally was telepathic, suggesting that the ability was widely known, if rarely encountered. Cally used her telepathy irregularly, most significantly to interrogate Blake when she ambushed him on Saurian Major, to voice her loneliness when overcome by sono vapour on the Ortega, to warn Blake of approaching guards on UP-Bounty, to help Blake convince Largo that Liberator carried four shuttles, to communicate to the moon discs on Zonda, to warn Ro of the Kommissar on Horizon, to warn Avon not to enter the control complex on Star One, to tell Avon that Liberator had been boarded in Volcano, and later to direct Dayna and Tarrant to Mori's position on Obsidian, to tell Vila to run from an approaching vehicle on Crandor, to reassure Zelda of Liberator's coming to Auron, and to inform Tarrant of the combat environment chosen by the computer for his duel with Vinni.
In Shadow and Death-Watch she expressed doubts about her ability to contact people on the surface of a planet from orbit, and in Volcano she had trouble making contact with Avon even though they were both on the Liberator together, albeit in different places. Contact with Zelda was possible under far greater distances, however, presumably due to what Zelda described as "optimum telepathic affinity". In Death-Watch Cally implied that the ability to contact an individual might be related to the degree to which s/he was known by the telepath.
She was telepathically contacted by the Lost, the Darkness, the Thaarn, the undead alien in the sarcophagus, and the Ultra (apparently, using the power of the Core). She also detected the inimical nature of Wanderer K47. The undead alien described a telepath as "rare", and the Ultra catalogued her "humanoid vertebrate, subcategory telepath". Dorian referred to her death making it more difficult to integrate the crew into a gestalt creature to absorb his corruption, and specifically cited her telepathy.
Other possibly telepathic beings included Zil and Sopron. Zeeona was instantly aware of her father's death despite the distance between them, so she and perhaps others or even all of her people may have had some telepathic ability. Tara of Goth's powers might also have had a telepathic basis.