La Plante said it was the "proudest moment" of her life
Writers Lynda La Plante and Margaret Drabble have received Royal honours at an investiture in Buckingham Palace.
La Plante was awarded a CBE for services to literature, drama and charity, while Drabble was made a dame.
La Plante is best known for writing the TV series Prime Suspect, which starred Dame Helen Mirren as the tough but troubled DCI Jane Tennison.
Drabble, whose books include Jerusalem The Golden and The Millstone, has said she may retire after writing 17 novels.
La Plante said it was the "proudest moment" of her life to be recognised for her writing career, which she turned to after working as an actress on TV series like The Sweeney and Minder.
"I'd always written but never contemplated it as a career, then one day I said, 'can I have a go at this?'"
She added that the CBE would enable her to do more charitable work on a "one-to-one" basis.
Drabble is the younger sister of novelist AS Byatt
"I think now with this honour I will be able to do a lot more, people will take it much more seriously and I just hope this new year will prove I can do a lot more."
Drabble, one of the UK's most acclaimed novelists, said: "I'm astonished to receive this, and thrilled."
She added: "I've always been a reader and writing still engages me more than anything else. I had three small children, it was company, I could talk to the world through my books."
Reflecting on her four-decade-long career, Drabble said: "The most popular of my books has been the Millstone, which I wrote in the 60s. That's the one that's done best around the world.
"But I always like the most recent and at the moment it's the Sea Lady, which I sometimes think will be my last because I've written an awful lot now so I might retire."