Metasurface holography has attracted much attention in recent years because of its practical applications including anti-counterfeiting, sensing, and lensing. However, most metasurface holograms have been constrained to rigid substrates which limit their out-of-the-lab value. Flexible holographic metasurfaces offer increased post-fabrication tunability as they can be bent or stretched, can be conformed to real-world non-flat surfaces, and are compatible with commercially viable roll-to-roll fabrication methods. This thesis describes how flexible holographic metasurfaces can be fabricated, their utility, and the novel phenomena that arise from them. In particular, it details a hologram retrieval algorithm for non-flat surface topologies, and how the topography determines the resultant symmetry properties of the holographic image. Furthermore, this thesis outlines a concept for replacing the bulky and complicated optics required for light sheet fluorescent microscopy with a simple holographic metasurface illuminated by a collimated beam. Two plasmonic meta-atom designs, both operating in reflection, are presented here, one for the visible wavelength range using nanorods and Pancharatnam-Berry phase-shifting, and the other for the millimetre wavelength range using c-rings. Extending the tools available for holography paves-the-way for advances in this field.