  Young stars and planetary systems form in molecular clouds. For classical T
Tauri stars (CTTS, F-K type precursors) the accretion disk does not reach down
to the central star, but it is truncated near the co-rotation radius. The inner
edge of the disk is ionized by the stellar radiation, so that the accretion
stream is funneled along the magnetic field lines. On the stellar surface an
accretion shock develops, which is observed over a wide wavelength range as
X-ray emission, UV excess, optical veiling and optical and IR emission lines.
Some of the accretion tracers, e.g. H\alpha, can be calibrated to measure the
accretion rate. This accretion process is variable on time scales of hours to
years due to changing accretion rates, stellar rotation and reconfiguration of
the magnetic field. Furthermore, many accreting systems also drive strong
outflows which are ultimately powered by accretion. Several components could
contribute to the outflows: slow, wide-angle disk winds, X-winds launched close
to the inner disk rim, and thermally driven stellar winds. In any case, the
outflows contain material of very different temperatures and speeds. The disk
wind is cool and can have a molecular component with just a few tens of km/s,
while the central component of the outflow can reach a few 100 km/s. In some
cases the inner part of the outflow is collimated to a small-angle jet. These
jets have an onion-like structure, where the inner components are consecutively
hotter and faster. The jets can contain working surfaces, which show up as
Herbig-Haro knots. Accretion and outflows in the CTTS phase do not only
determine stellar parameters like the rotation rate on the main-sequence, they
also can have a profound impact on the environment of young stars. This review
concentrates on CTTS in near-by star forming regions where observations of high
spatial and spectral resolution are available.
