Strongly interacting quarks, anti-quarks and gluons are confined to hadrons
at low energies, whereas a deconfining phase transition to a new phase of
matter occurs at higher energies. In the early stages of relativistic heavy
ion collisions such high temperatures are achieved and the Quark Gluon
Plasma (QGP) is produced. As it turns out, predicitions based on ideal that
is non-viscous hydrodynamics agree surprisingly well with experimental
results. This agreement is slightly improved by including viscous effects.
Transport coefficients characterizing these lowest order viscous effects are
the shear and bulk viscosities. I will talk about how kinetic theory and in
particular the Boltzmann equation can be used to perturbatively calculate
the transport coefficients of QGP to leading order in the strong coupling
constant.