The magnetic and optical anisotropies of evaporated iron-nickelfilms deposited at an angle to the substrate normal are found to besensitive to the rate of deposition and the orientation of themagnetizationMduring deposition. It is postulated that crystalliteelongation toward the vapor beam or in the direction ofMoccurs.Study of spatial inhomogeneities in the normal-incidenceM-inducedanisotropy fieldHkis an aid in understanding the origin ofthis anisotropy and the switching behavior of films. Small-angledispersion ofHkis attributed to local deviation from isotropy ofthe isotropic tension present in films; measurements support thismodel. Magnitude dispersion is estimated from rotational hysteresisexperiments. Large-angle dispersion of a special type has beenidentified wherein certain regions of a film have an easy axisperpendicular to the field present during deposition, i.e.,Hkisnegative in these regions. For alloy compositions within a fewpercent of 83% Ni and 17% Fe, the normalized wall coerciveforcehw = Hw/Hkhas significance beyond the defining concepts.Thus,hwis a measure of resonance linewidth and an internal fieldinferred from resonance data; forhw>1, a unique “locking”phenomenon occurs. Bitter-pattern studies of quasi-static switchingshow that negative-Hkregions are present and thathwis insome sense a measure of these regions. A tentative model forM-induced anisotropy which qualitatively explains both positiveand negativeHkis proposed which invokes directed pairs of ironatoms and strain anisotropy arising from elongated crystallites.In nonlocking films, quasi-static switching by coherent rotation isbroken up by labyrinth domains consisting of alternating regionsof switched and unswitchedM. Propagation of these domains ispostulated to be caused by dispersion in the magnitude and orientationofHk. If a pulsed reversing field exceeds the switchingthreshold of all regions of the film, a transition from labyrinthswitching to coherent switching should occur, as has been observedexperimentally.