Optical fibers technology has experienced a tremendous growth and advancement over the past several decades, not only in transmission systems for communications (where nowadays totally dominate especially at the high performances level) but also in the sensing field. For this reason, there is an ever increasing need to add new functionalities and improve the performances, through the integration on the optical fibers of advanced functional materials providing the control and manipulation of light at nanoscale. Both metallic and dielectric nanostructures (in particular photonic and plasmonic crystals) seem to meet that need since they offer unprecedented opportunities for sub-wavelength field confinement and resonant field enhancement. Many prestigious research groups in the photonic community are thus focusing their efforts to fuse together the world of nanotechnologies with optical fibers, leading to the …