  We present a detailed study of the physical properties of the nebular
material in four star-forming knots of the blue compact dwarf galaxy Haro 15.
Using long-slit and echelle spectroscopy obtained at Las Campanas Observatory,
we study the physical conditions (electron density and temperatures), ionic and
total chemical abundances of several atoms, reddening and ionization structure,
for the global flux and for the different kinematical components. The latter
was derived by comparing the oxygen and sulphur ionic ratios to their
corresponding observed emission line ratios (the $\eta$ and $\eta$' plots) in
different regions of the galaxy. Applying the direct method or empirical
relationships for abundance determination, we perform a comparative analysis
between these regions. The similarities found in the ionization structure of
the different kinematical components implies that the effective temperatures of
the ionizing radiation fields are very similar in spite of some small
differences in the ionization state of the different elements. Therefore the
different gaseous kinematical components identified in each star forming knot
are probably ionized by the same star cluster. However, the difference in the
ionizing structure of the two knots with knot A showing a lower effective
temperature than knot B, suggests a different evolutionary stage for them
consistent with the presence of an older and more evolved stellar population in
the first.
