Correspondence sent to Ursula Moray Williams in her professional capacity as a children's author and illustrator, including correspondence regarding the publication of her books from various British and American publishers; correspondence regarding appearances and talks at various public events, including literary festivals, and visits to various schools; and correspondence from various professional organisations which Williams supported or was involved with during her career as a writer. Unfortunately, only the incoming letters to Williams survive, and there are no copies of her outgoing letters. In many cases, it would also appear that what survives is only a small portion of the correspondence received by Williams, either as a result of deliberate weeding on her part or through accidental loss.
The correspondence has been roughly grouped into several sub-series and files based on the type of correspondent. Further details on each grouping are given at lower levels.