Julian Penkivil Slade was an English writer of musical theatre, best known for the show Salad Days, which he wrote in six weeks in 1954, and which became the UK's longest-running show of the 1950s, with over 2,288 performances.

Salad Days is a musical with music by Julian Slade, and with book and lyrics by Dorothy Reynolds and Julian Slade. The musical was initially performed in 1954 in the UK in Bristol and then in the West End, where it ran for 2,283 performances.