Oriented CdI2 has been prepared in a deposited Langmuir-Blodgett (LB) film by the reaction of gaseous HI with a 20-layer LB film of cadmium arachidate. Attenuated total reflectance Fourier transform IR spectroscopy shows that the conversion goes to completion, while X-ray photoelectron spectroscopy analysis of the HI-exposed cadmium arachidate film reveals a Cd:I ratio consistent with the CdI2 Stoichiometry. Electron diffraction shows that the CdI2 is oriented exclusively with its [001] axis normal to the LB film basal plane and for domains ranging up to several microns has a preferred alignment about the [001] axis. The results suggest that the organic template plays a role in orienting the CdI2 within the LB plane and that some degree of lattice matching exists between the LB template and the (001) face of CdI2. The oriented synthesis described here is in contrast with previous attempts at template-directed syntheses using deposited LB films which have resulted in the mediation of particle size only and not particle orientation. The difference here may be that CdI2 has a layered structure in the bulk, crystalline phase which complements the LB film structure.