  The evidence of a relation between the mass accretion rate and the disk mass
is established for young, Class II pre-main sequence stars. This observational
result opened an avenue to test theoretical models and constrain the initial
conditions of the disk formation, fundamental in the understanding of the
emergence of planetary systems. However, it is becoming clear that the planet
formation starts even before the Class II stage, in disks around Class 0 and I
protostars. We show for the first time evidence for a correlation between the
mass accretion rate and the disk mass for a large sample of Class I young stars
located in nearby (< 500 pc) star-forming regions. We fit our sample, finding
that the Class I objects relation has a slope flatter than Class II stars, and
have higher mass accretion rates and disk masses. The results are put in
context of the disk evolution models.
