[en] The magnetic properties of the cubic C-15-type Laves phases NpAl₂ and NpOs₂ have been studied in fields up to 80 kOe by means of bulk magnetization, nuclear γ-ray resonance (NGR), and neutron-diffraction techniques. Both materials are ferromagnetic. In NpAl₂, the bulk moment mu-bar₀ = 1.21μ/subB/, whereas the 5f moment, as determined by NGR and neutron-diffraction methods, is 1.50μ/subB/. NpAl₂ is a localized ferromagnet with a small high-field susceptibility and, in common with all other actinide ferromagnets examined so far, exhibits a negative conduction-electron polarization. In contrast, NpOs₂ behaves like an itinerant ferromagnet with a large high-field susceptibility, and a total moment mu-bar₀ = 0.44μ/subB/. If the NGR and neutron-diffraction measurements are interpreted in terms of localized 5f moments, they give values for the Np moment in NpOs₂ of 0.40μ/subB/ and 0.25μ/subB/, respectively. A qualitative discussion is presented to argue that the 5f electrons in NpOs₂ are spatially delocalized and that this will reconcile the discrepancies between the magnetic moments determined by the three techniques. Some additional results for NpMn₂ and NpNi₂ are also reported