St John's headquarters in Gonville is so overflowing with books that some have to be stored in a shipping container.
There's an entire storeroom filled with boxes of books; and boxes line the hallway, are stacked in corners and poke out from under tables.
So it's just as well that St John is having a book sale this week. The sale will be held from Thursday to Saturday, and will include a wide range of books, magazines, CDs, and games and puzzles.
Organiser Jenny Burkett said the task of organising and running the book sale was so big that it took 40 volunteers to get the job done.
"We are very lucky to have such enthusiastic volunteers. We've probably got hundreds of thousands, if not millions, of books here - but we can't sell them all in one sale."
Mrs Burkett said the books came from public donations and estates, and some were ex-library books.
She said the book sale was very important for St John Wanganui's funding.
"Our ambulance service gets some government funding, but our community programmes get none. So the money we raise goes towards those.
"We've just purchased a wheelchair for our health shuttle, and it's our book sales that enable us to do that sort of thing."
Mrs Burkett said the book sales were usually well supported by the public. She hoped this sale would raise about $3000.
The next book sale will be in January 2018.
+St John book sale will be held at the St John headquarters, 25 Tawa St, at the following times: Thursday 6pm-9pm, Friday 10am-6pm, Saturday 10am-4pm.