  We study the non-boost-invariant evolution of a quark-gluon plasma subject to
large early-time momentum-space anisotropies. Rather than using the canonical
hydrodynamical expansion of the distribution function around an isotropic
equilibrium state, we expand around a state which is anisotropic in momentum
space and parameterize this state in terms of three proper-time and
spatial-rapidity dependent parameters. Deviations from the Bjorken scaling
solutions are naturally taken into account by the time evolution of the
spatial-rapidity dependence of the anisotropic ansatz. As a result, we obtain
three coupled partial differential equations for the momentum-space anisotropy,
the typical momentum of the degrees of freedom, and the longitudinal flow.
Within this framework (0+1)-dimensional Bjorken expansion is obtained as an
asymptotic limit. Finally, we make quantitative comparisons of the temporal and
spatial-rapidity evolution of the dynamical parameters and resulting pressure
anisotropy in both the strong and weak coupling limits.
