Kate, Princess of Wales has participated in St. Patrick's Day festivities in the UK since 2012.

Kate honors the Irish Guards by distributing shamrocks for good luck, continuing a royal tradition.

Kate wears a gold Cartier shamrock pin which belongs to the Irish Guards.

The shamrock pin has textured gold leaves and is adorned with an emerald in the center.

Kate usually wears shades of pine and emerald green to this event.

Green is a go-to color for Kate because it matches her eye color.

Kate's hats and fascinators for this event range from green to neutral shades like black or brown.

In 2015, Kate strayed from tradition and opted for an all-brown ensemble.

Kate has departed from traditional green this time as a nod to one of her new royal duties.