Gray is the yin and yang altogether. It's the feminine in the way it nurtures and supports surrounding colors. It's also the masculine, an ominous sky and battleships. In the tonal palette it represents Switzerland: Neutral, cool, subdued, sophisticated, elegant, corporate, and serious.
In the right hands it is grace, as in the designs of David Hicks (the two below) which are nothing like corporate.
Gray socializes well with other colors. It is a peacemaker. It pulls back bright colors and grounds darks and lights. It's most agreeable: In a family of purple, pink, and yellow it is a kind of visual middle child.
It's the epitome of diversity and the ultimate equalizer. It is also bold without being assertive. An abused gray can easily turn into a drone: drab, dull, and dead. Yet within it is always the potential for the spectacular.
It is simple, understated elegance, refined enough to never call attention to itself.
In the garden, it stands back and launches the green and red forward.
It makes even a hand-made look natural in the landscape.