  We present electron collision strengths and their thermally averaged values
for the forbidden lines of the astronomically abundant doubly-ionized oxygen
ion, O^{2+}, in an intermediate coupling scheme using the Breit-Pauli
relativistic terms as implemented in an R-matrix atomic scattering code. We use
several atomic targets for the R-matrix scattering calculations including one
with 72 atomic terms. We also compare with new results obtained using the
intermediate coupling frame transformation method. We find spectroscopically
significant differences against a recent Breit-Pauli calculation for the
excitation of the [O III] lambda 4363 transition but confirm the results of
earlier calculations.
