Single crystals of rutile, grown by the Verneuil method, have been chemically thinned and examined by electron transmission microscopy. The density and distribution of dislocations agree with that expected from etch pit data. This density is at least two orders of magnitude below that for rutile films formed by oxidizing titanium carbide. The etching of dislocations and stacking faults is described.Some preliminary results of high‐temperature studies in the microscope are reported. These include the discovery of a hitherto unknown slip system, {001} ⟨100⟩.