  To identify some way to measure the quark transversity, this thesis analyzes
one-particle and two-particle inclusive deep inelastic scattering, where one
and two of the outgoing hadrons are detected in coincidence with the electron.
It is shown that transversity can be measured in the above processes, in
connection with three different fragmentation functions: the first one requires
the observation of an unpolarized final state hadron with transverse momentum
(Collins function), the second requires the observation of the interference
between the s- and p-wave production of two hadrons, the third requires the
observation of pure p-wave two-hadron production, or equivalently of a spin-one
resonance. All these fragmentation functions fall in the category of T-odd
fragmentation functions: they require the presence of final state interactions,
or else they are forbidden by time-reversal invariance. The last part of the
thesis looks at the possibility of modeling this kind of fragmentation
functions and investigates whether they can be large enough to allow the
extraction of transversity.
