Sea Change is a realistic children's adventure novel by Richard Armstrong, first published by Dent in 1948 with line drawings by Michel Leszczynski[1] and promoted as "A novel for boys".

Armstrong had served 17 years in the Merchant Service, in "tramps, steamers, liners, colliers and tankers" after World War I, beginning at the same age.

He and Sea Change won the annual Carnegie Medal from the Library Association, recognising the year's best children's book by a British subject.

[2] Cam Renton has been an apprentice seaman for a year when he arrives at Liverpool to join the crew of the Langdale, a cargo ship heading for Barbados and the Spanish Main.

Afterward Cam starts to work and study in earnest, and his knowledge of navigation and semaphore are put to use when he becomes part of a skeleton crew aboard a salvaged derelict.

"The novel suggests the continuance of a set of attributes which define manliness as well as maintaining the status quo within a society recovering from the upheaval of a World War.

As well as having a command of the details of shipboard life, Armstrong has a profound understanding of how a young man thinks, and skilfully shows Cam's essential decency and his struggle to come to terms with the world he finds himself in.