Bipolar outflows are a basic ingredient in the process of star
 formation. The Extremely-High-Velocity (EHV) molecular flows are
 particularly interesting, since they represent the *youngest* stage of
 the bipolar outflow phenomenon. Such young outflows are associated with
 the youngest (proto)stellar objects known so far, and are still deeply
 embedded in the parent molecular clouds. Shock waves generated by the
 outflowing motions are the origin of highly-excited neutral (or
 weakly ionized) gas that is best observed in the infrared. In fact,
 the most important cooling lines are expected to occur
 in the wavelength range of the ISO spectrometers.

 We propose to obtain high-sensitivity spectra toward prototypical
 young molecular outflows. Full grating spectra will be obtained
 toward the most important sources (L1157, IRAS2005, and IC348). Moreover,
 since young outflows exhibit EHV molecular lines of about 100 to 200
 km/s, a study or their kinematics is possible with the ISO instruments. Thus,
 we propose to obtain high-spectral resolution (FP) observations of some
 key cooling lines ([OI], [CII]) toward some positions carefully selected
 from our previous molecular (mm, near-IR) studies.

 The proposed observations complement the ISO Central Programme
 observations which are mainly addressing  much more
 evolved, bipolar outflows (similar to L1551). The ISO observations of
 the youngest outflows proposed here are expected to provide important
 insights in the processes of star formation, and will be very
 important for the understanding of the genesis and evolution of
 bipolar outflows in general.