Several MSDP instruments are used in solar physics to observe simultaneously 2D-fields in a number of wavelengths.
We describe briefly the needs of 3D-data in solar physics, the different spectroscopic methods in use, and the principle of MSDP spectrographs. We discuss the relationships between spectral resolution, field of view and efficiency. We summarize the capabilities of the instruments, either presently working (Meudon, Pic du Midi, Tenerife and Wroclaw), or associated with the THEMIS project.
The solar results take into account the main performances of the MSDP, that is to say the very high spatial resolution and the high speed to cover a wide area on the sun within a short time (coordinated campaigns with space probes).
We conclude by a brief discussion of the capabilities which could be expected from the MSDP in night-time astronomy.