Comfort and practicality are the core requirements of the Queen's wardrobe but several other criteria must be met when dressing the sovereign, a royal designer reveals in a new book.
Fans are used to test how lightweight fabrics will move in a breeze, presumably to ensure the monarch's modesty, and clothes must not crease as 86-year-old Elizabeth steps from a car to be met by swarms of photographers.
Angela Kelly has been designing at Buckingham Palace for 18 years and in her book, Dressing The Queen: The Jubilee Wardrobe, she reveals the precision planning behind each outfit.
Ms Kelly is part of a team believed to total 12 who manage the Queen's wardrobe. They include three dressmakers, a milliner, and four "dressers".
Ms Kelly sketches multiple designs for a piece of fabric and once approved by the Queen, a prototype is made using a mannequin fitting the monarch's measurements.
Ms Kelly says the sovereign taught her how to select fabrics.
"I will squeeze and test the sample in my hands before smoothing it out once more," she says. "If the material remains creased and crumpled, it will be of no use."
Colours are carefully selected to complement specific occasions and ensure the Queen can always be easily seen by admirers and photographers.
Each outfit is matched with a hat and umbrella, which must also meet strict specifications and measurements.
In rain, the Queen uses clear umbrellas so she can still be seen, but the brolly trim and hook handles must match her dress.
"After 6pm, the Queen does not usually wear a hat but may wear a headpiece, and to the evening state banquets, a tiara," Ms Kelly says.
The designer reveals the Queen favours 5cm heels for hard surfaces; three-quarter length, fitted sleeves; a plain white handkerchief with motif for daytime official duties; and zips so numerous dress changes do not wreak havoc with her hair and make-up.