Convection is an important phenomenon in the atmospheres of A-type and cooler
stars. A description of convection in ATLAS models is presented, together with
details of how it is specified in model calculations. The effects of changing
the treatment of convection on model structures and how this affects observable
quantities are discussed. The role of microturbulence is examined, and its link
to velocity fields within the atmosphere. Far from being free parameters,
mixing-length and microturbulence should be constrained in model calculations.Comment: 7 pages, 6 figures. To appear in the proceedings of the Workshop
"ATLAS 12 and related codes", Trieste, July 11-15, 200
