We present preliminary results of our programme aimed at the study of a sam
ple of ULIRGs on the basis of two-dimensional (integral field) optical spec
troscopy and multi-frequency high spatial resolution HST imaging. In partic
ular, we show here results on Mrk 273 and IRAS 12112+0305 recently obtained
with the INTEGRAL system at the 4.2 m WHT. A brief comparison with the HST
images is also made.