We have observed two phase transitions, at T1 almost-equal-to 7 K and T2 almost-equal-to 5 K in the localized magnetic moment compound UPd3. Several superlattice peaks of the type (h + 1/2, 0, l) have been investigated using polarised neutrons. The transition at T1 has a structural character, whereas that at T2 has both structural and magnetic components.