  We are obtaining deep multiwavelength data of a sample of nearby blue compact
dwarf galaxies (BCDGs) combining broad-band optical/NIR and H$\alpha$
photometry, optical spectroscopy and 21-cm radio observations. Here we present
HI results obtained with the Australia Telescope Compact Array for some BCDGs,
all showing evident interaction features in their neutral gas component despite
the environment in which they reside. Our analysis strongly suggests that
interactions with or between low-luminosity dwarf galaxies or HI clouds are the
main trigger mechanism of the star-forming bursts in BCDGs; however these dwarf
objects are only detected when deep optical images and complementary HI
observations are performed. Are therefore BCDGs real isolated systems?
