  We examine the correspondence between the anti-de Sitter (AdS) description of
conformal field theories (CFTs) and the unparticle description of CFTs. We show
how unparticle actions are equivalent to holographic boundary actions for
fields in AdS, and how massive unparticles provide a new type of infrared
cutoff that can be simply implemented in AdS by a soft breaking of conformal
symmetry. We also show that processes involving scalar unparticles with
dimensions d_s<2 or fermion unparticles with dimensions d_f<5/2 are insensitive
to ultraviolet cutoff effects. Finally we show that gauge interactions for
unparticles can be described by bulk gauge interactions in AdS and that they
correspond to minimal gauging of the non-local effective action, and we compute
the fermion unparticle production cross-section.
