European Southern Observatory, Karl-Schwarzschild-Str 2, D-85748 Garching, Germany
ISO observed a wide range of active galaxy types from distant quasars
to LINERS, providing more extensive and detailed photometry than IRAS
plus images and the first high quality spectra over the complete 2.5 -
200
m range. In this brief review I will focus on a few selected
scientific topics where early results indicate that ISO is likely to
make a significant impact. These include the nature of the far
infrared emission of quasars and radio galaxies with implications for
unification models; origin of the hot dust continuum and PAH feature
emission in Seyfert galaxies; shape of the UV ionizing spectrum,
limits on shock excitation and origin of line asymmetries in Seyferts
inferred from high excitation infrared fine structure lines; IR pumping
of OH megamasers and the detection of highly obscured AGNs using
infrared spectroscopic diagnostics.