Structured light has proven useful for numerous photonic applications ranging from classical to quantum optics. Conventional structured-light generation requires multiple cascaded phase- and polarisation-sensitive elements, imposing major challenges for system integration and device applications. Metasurfaces composed of subwavelength meta-atoms provide an attractive platform for manipulating the near- and far-field electromagnetic waves. Ultrathin metasurfaces have been widely used to generate, detect, and manipulate various kinds of structured light fields, through advanced light control over the amplitude, phase, polarisation, and other degrees of freedom of light. Meanwhile, artificial intelligence, the original concept in computer science, has been deployed in photonics, providing an efficient solution to the metasurface design and optimisation. This focused session aims to attract important contributions to the fields of nanophotonics and metasurfaces, highlighting new topics on metasurfaces, including but not limited to, structured light manipulation, inverse photonic design, and artificial intelligence.