20% of visits to the veterinary may be due to otitis and although, in general, they do not represent a serious condition for the animal, they are very unpleasant and insidious processes if they are not treated suitably and guidelines for management and control are not established. This work presents a selection of clinical cases, in their majority of otitis, which can be diagnosed in dogs and cats, and completes the information with anatomic, etiopathogenic, clinical and analytical aspects. Finally, it gives advice about the external and systemic treatments that may be applied in each case.