Rotation and properties of A- and B-type chemically peculiar stars

Main-sequence chemically peculiar stars of spectral types A and B, which are characterised by photospheric abundance anomalies resulting from element segregation in the stellar outer layers, rotate slower than normal stars of similar temperatures. The mechanisms by which such slow rotation is achieved are not well understood yet; different processes may be involved for different types of chemical peculiarities, including stellar magnetic fields and multiplicity. Relevant existing observational data are reviewed.