Using an effective relaxation time model, the effects of ion-ion and ion-neutral collisions on quasi-linear ion heating by the current-driven ion cyclotron instability in the high-latitude ionosphere have been studied. For conditions typical of the high-latitude lower (200--300 km) F region ionosphere, it is found that the combined effects of ion-neutral and ion-ion collisions tend to isotropize (T⊥/T∥~1) the perpendicular (T⊥) and parallel (T∥) ion temperatures on time scales of the order of several tens to hundreds of NO+ cyclotron periods for wave amplitudes eϕ/Te=0.2. Here, ϕ is the wave electrostatic potential, Tc the electron temperature (in energy units), and e is the electron charge. In addition, for the high-latitude upper (600 km) F region ionosphere it is found that stronger anisotropy (T⊥/T∥>3) can be sustained even in the presence of ion collisions by waves with amplitudes eϕ/Tc=0.2. For larger-amplitude waves eϕ/Tc=0.4, we find that the heating is weakly anisotropic at low altitudes (200--300 km) and strongly anisotropic at higher (600 km) altitudes. In both wave amplitude regimes (0.2 and 0.4), we find perpendicular ion heating factors ~2--10 for altitudes in the range 300--600 km, with the larger perpendicular heating occurring at higher altitudes and larger wave amplitudes. We compare our results with recent rocket and satellite observations in the high-latitude ionosphere. ¿ American Geophysical Union 1989