Lady Penelope Creighton-Ward is a fictional character introduced in the British 1960s Supermarionation television series Thunderbirds, which was produced by AP Films (APF) for ITC Entertainment. The character also appears in the film sequels Thunderbirds Are Go (1966) and Thunderbird 6 (1968), the 2004 live-action film Thunderbirds and the CGI remake series Thunderbirds Are Go. In the world of Thunderbirds, Penelope is employed by the secret organisation International Rescue as its London field agent.

Thunderbirds is a British science fiction television series created by Gerry and Sylvia Anderson, filmed by their production company AP Films (APF) and distributed by ITC Entertainment. It was made between 1964 and 1966 using a form of electronic marionette puppetry combined with scale model special effects sequences. Two series, totalling thirty-two 50-minute episodes, were filmed; production ended with the completion of the sixth episode of the second series after Lew Grade, the Andersons' financial backer, failed in his bid to sell the programme to American network television.