Sentenced to Prism (1985) is a science fiction novel by American writer Alan Dean Foster, a stand-alone entry in his Humanx Commonwealth series of books.

Set in the Humanx Commonwealth, Prism is a unique planet because its ecosystem contains both silicon-based and carbon-based life.

Evan Orgell, a management troubleshooter sent to Prism to investigate the disappearance of a research group, finds himself fighting for his survival in this strange crystalline environment after his specialized environment suit succumbs to the local elements.

With the help of a caterpillar-like creature named A Surface of Fine Azure-Tinted Reflection With Pyroxin Dendritic Inclusions (which Evan chooses to call simply "Azure", much to his strange new friend's disappointment) he must grow to overcome his prejudices, his assumptions, and his preoccupations to relearn what life, communication, companionship, government, and even his own bodily form mean to him.

He and his new-found friends must overcome multiple treacherous acts by his own race in order to survive and thrive on the beautiful, but deadly, planet.