  Direct measurements of magnetic fields in low-mass stars of spectral class M
have become available during the last years. This contribution summarizes the
data available on direct magnetic measurements in M dwarfs from Zeeman analysis
in integrated and polarized light. Strong magnetic fields at kilo-Gauss
strength are found throughout the whole M spectral range, and so far all field
M dwarfs of spectral type M6 and later show strong magnetic fields. Zeeman
Doppler images from polarized light find weaker fields, which may carry
important information on magnetic field generation in partially and fully
convective stars.
