  The isothermal dynamical evolution of a clumpy and turbulent molecular cloud
region and its fragmentation into a protostellar cluster is investigated
numerically. The effect of different initial density and velocity
distributions, generated from different realizations of a Gaussian random field
with power spectrum P(k) ~ k^{-2} is investigated. As a result of the interplay
between gas pressure and gravitational forces, a quasi-equilibrium clump mass
spectrum emerges with a power-law distribution dN/dM ~ M^{-1.5}, independent of
the initial conditions. Being part of a complex network of filaments,
individual clumps are elongated, centrally condensed objects with 2:1 to 4:1
axis ratios with outer r^{-2} density distributions.
  Dense, Jeans-unstable gas clumps collapse and form protostellar cores which
evolve through competitive accretion and $N$-body interactions with other
cores. In contrast to the clumps, the core mass spectrum is best described by a
log-normal distribution which peaks approximately at the average Jeans mass of
the system. Scaled to physical conditions typical for star-forming molecular
clouds, the mass function is in good agreement with the IMF of multiple stellar
systems.
  The final dynamical state of the newly formed stellar cluster closely
resembles observed young stellar clusters. It has a core/halo structure which
is typical for collision dominated N-body systems. The 2-point correlation
function of the spatial stellar distribution can be described by two power-laws
with a break in the slope at the transition point from the binary to the
large-scale clustering regime. The protostellar cluster is marginally bound.
