Shape-shifting is the ability to alter one's appearance. Many beings have this ability, and various technologies can also create a similar effect.
- Adria was able to use her pendant device to disguise herself as Osric while traveling with SG-1. This device most probably used solid holograms to create the effect.
- Standard Replicators can link their blocks together in different ways to change their shapes, allowing them to perform a variety of different tasks.
- Asurans and the very similar Human-form Replicators can, in a similar way, link their nanites together in different ways to form different shapes. As nanites are so small, they can form much more complex shapes, even to the point of being able to imitate people. Unlike standard replicators they can also change their colors. Most advanced sensors can still distinguish between nanite bodies and organic ones, however.
- Stragoth Mimetic imaging devices can create seemingly solid holographic projections of others around the users, in a similar way to Adria's pendant. They also change the user's voice to match that of the illusion.
- Salish Spirits appear to use technology to allow them to change their shape at will, even to non-humanoid forms such as animals.
- Ascended beings can change their shape to mimic anything, or become pure energy. No known sensors can distinguish an ascended being from a regular human when they are in human form.
- Unity can mimic faces and, if powerful enough, whole people.
- Grag has shown to transform into various individuals, either male, female or from other races as well as appearing as if he was killed.