Magnetic nanowires and nanoparticles exhibit multifunctional properties and are useful in a broad range of applications such as drug or gene delivery, or for magnetic imaging. In contrast, there has been very little work reported on magnetic nanotubes, which represent a new class of anisotropic multifunctional nanoparticles. By coating the inner or outer nanotube wall with oxides, polymers, biomolecules or metals, a broad range of physical and chemical properties may be realised within a single structure. In comparison with nanowires, nanotubes have very low mass and may therefore be more suitable for applications in ferrofluids or drug delivery. We investigate novel approaches on the fabrication of multifunctional nanowires and nanotubes by using highly-ordered porous alumina templates, polymer infiltration, and electrochemical deposition techniques. The emphasis is on the magnetic characterisation of ferromagnetic nanotubes and nanowires. The experimental results are complemented by computer simulations and theoretical investigations which are performed also in colaborations with Chilean groups.