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Recent years have witnessed a growing interest, theoretically as well as experimentally, in space-variant polarization manipulation for obtaining vectorial beams. In general, vectorial beams are defined as beams having space-variant (transversely nonuniform) polarization state. In this lecture we present new methods for designing, realizing and analyzing nonuniformly polarized and partial polarized beams using quasiperiodic microand nanostructured optical elements, (space-variant subwavelength gratings) [1]. Our approach is based on determining the local period and direction of the grating at each point, forming space varying polarizers or waveplates that convert uniform polarized light into any desired space-variant polarization. Linear polarized light with axial symmetry [2], vectorial Bessel beams and rotating vectorial vortices are demonstrated [3]. In addition, unique methods based on subwavelength gratings for rapid polarization measurement [4], spatial-polarization state scrambling for image encryption, vectorial vortex mode transformation for a hollow waveguide [5], and sophisticated polarization-dependent optical elements [1] are introduced. Space-variant polarization state manipulations of thermal emission are also investigated [6]. It is shown that radiation into a narrow spectral band can be obtained by exploiting surface excitations such as plasmons or phonon polaritons. Finally, we will briefly review our recent investigation of plasmonic microcavities for near field optical manipulations.