The characterisation as well as improvement of various photonic devices, functional nanomaterials and quantum structures heavily relies on advanced optical tools. These tools typically incorporate suitable light sources and detection schemes to probe properties of the target system optically. Through special measurement techniques, one can for instance obtain optical images with high spatial resolution to map features of a sample, or read out spectral properties with sufficient temporal resolution in order to achieve insights into charge-carrier dynamics. While in many situations, the basic material response is of interest when irradiating light onto a sample, some techniques address a material’s nonlinearities or composition, the emission’s coherence or angle-dependencies, or a structure’s phonon modes or magneto-optical properties. In this chapter, numerous optical measurement techniques are summarised which can be useful in the field of semiconductor photonics, particularly with an emphasis on the characterisation of two-dimensional semiconductors and quantum structures. Here, practical examples from the author’s works may encourage further reading of expert literature on these subjects.