Like data encryption, secret sharing is an important method of protecting secret messages. However, the basic ideas of secret sharing and data encryption are radically different. In this paper, a new method for secret sharing is proposed that focuses on image data. It is called the virtual image sharing method (VISM). It is basically derived from the virtual image cryptosystem. According to our experiments and security analyses, VISM can divide a secret image into a large number of different shadows which are guaranteed to be significant images. Illegal users cannot detect whether they are real images or not. VISM also guarantees the security of the secret image because no one is able to reconstruct any piece of the secret image without possessing all of the shadows. Besides camouflage and security, VISM has two other benefits. One is its compression ability. The total size of shadows can be smaller than that of the secret image. The other benefit is its efficiency. VISM avoids the painstaking task of applying complex operations or techniques.