  We review from the point of view of nonextensive statistics the ubiquitous
presence in elementary and heavy-ion collisions of power-law distributions.
Special emphasis is placed on the conjecture that this is just a reflection of
some intrinsic fluctuations existing in the hadronic systems considered. These
systems summarily described by a single parameter q playing the role of a
nonextensivity measure in the nonextensive statistical models based on Tsallis
entropy.
