The M81 group has great advantages for dwarf galaxy studies: it has about three times the dwarf content of the Local Group but is at only about a quarter of the Virgo cluster distance. We searched for HI in 23 optically selected dwarf members and possible members of the M81 group with the Nançay decimetric radio telescope in the velocity range of −529 to 1826 km s−1 with considerably better sensitivity (2–4 mJy rms.) than previous surveys. Half the objects observed are irregular dwarfs, expected to be HI-rich and detectable at Nançay if at the distance of the M81 group (4 Mpc).