Conversation so far:
What is Doctor Who in relation to Terrance Dicks?
BBC science-fiction TV series Doctor Who
Are there any other interesting aspects about this Terrance Dicks article on Doctor Who?
Terrance Dicks formed a highly productive working relationship with incoming Doctor Who producer Barry Letts, serving as script editor on all of Letts's five seasons as series producer.

Question: How long did he work on the series?
Self-contained rewrite: How long did Terrance Dicks work on the Doctor Who series?