Kate has fun with her hat styles, and donned a cowboy hat in Canada. Photo: PA
The association was formed in 1908, and is one of the oldest - and most trusted - in the industry.
Duchess Kate wore Rose Cory for Christmas Day at Sandringham. Photo: PA
It is their third annual Hat Person of the Year award, with Johnny Depp and Brad Pitt being previous winners.
Since her engagement in November 2010, the Kate was a worthy winner? Leave your thoughts below...