We present novel electrospinning-based methodologies to fabricate nanofibers (NFs) functionalized with metal nanoparticles (NPs). The composites have the potential as building blocks of functional fabrics with antimicrobial and catalytic properties for biomedical, filtration, sensor and catalytic applications. In one method, the electrospinning polymer acts as the reducing, protecting and templating agent for the NPs at ambient conditions, hence a genuine one-step process via electrospinning. An organic solvent- and corrosive reducing agent-free model system involving poly(ethylene oxide) (PEO)-AgNO₃-water system to generate Ag NP-PEO polymer NFs via electrospinning all in one-step at ambient conditions, is presented. We report interesting phenomena such as NP protrusions and NP alignment on the NF surface, both of which are found to be primarily associated with the applied electrical field. Secondly, we report the use of these metal NP-functionalized NFs as templates to fabricate hollow fibers (nanotubes/ microtubes) loaded with Ag nanoparticles (NPs) by atomic layer deposition (ALD). The resulting Ag NPs are spherical, crystalline and are well-dispersed within the nanotubes as observed from TEM and XRD analyses. And finally, we describe the decoration of polymer NF surfaces with metal nanostructures using a self-assembling technique.