Magnetometry based on nitrogen-vacancy (NV) spins in diamond has emerged as a powerful tool for probing condensed matter phenomena1 by mapping spins and charges in the nanoscale. In this talk I will focus on how we utilize scanning NV magnetometry, in which we use a NV sensor spin(s) that are shallowly embedded in the tip of a diamond scanning probe, to map (in)coherent spin waves – the elementary excitations of coupled spins in magnetically ordered materials – in thin magnetic insulators and discuss how NV spins enable the extraction of fundamental superconducting properties. Firstly, I will discuss imaging (in)coherent spin waves in a thin film magnetism insulator, where I will show how microwave excitation of low-wavenumber spin waves leads to a high-density and, most surprising, a unidirectional gas of incoherent magnons2 . I will also show how we can use our single-NV sensor as a wavelength filter to characterize frequency-degenerate spin wave modes3 . I will then discuss current progress towards probing spin waves in 2D magnets. Secondly, I will discuss current progress towards probing diamagnetism in a superconducting strip, with underlying motivation for understanding electronic transport in quantum devices. I will show that the degree of magnetic field shielding by the superconducting strip is dimension dependent, enabling the extraction of the London Penetration depth, as further supported by characterizing the magnetic field profile of Abrikosov vortices. These results reveal the power of scanning NV-magnetometry as a tool for magnetic field imaging over a wide detection range spanning DC to GHz. Whilst showcasing that (1) coherently driven, low-wavenumber spin waves are efficient generators of a non-equilibrium magnon gas in target directions, (2) nanoscale control over the NV-sample distance enables wavenumber-selective imaging of magnetization oscillations and (3) magnetic imaging of diamagnetism and fluxons enable the extraction of key superconducting material properties. Our results open new avenues for realizing 2D spin wave devices and for using NVs centres as diagnostic tools for superconducting qubit diagnostics. References: [1] F. Casola et al. Nature Reviews Materials 3, 17088 (2018). [2] B. G Simon, S. Kurdi et al. Nano Letters 21, 8213 (2021). [3] B. G Simon, S. Kurdi et al. Nano Letters 22, 9198 (2022).