  The profile of the differential rotation together with the sign of the
alpha-effect determine the dynamo wave direction. In early models of the solar
dynamo the dynamo wave often leads to a poleward migration of the activity
belts. Flux transport by the meridional flow or the effect of the surface shear
layer are possible solutions. In a model including the corona, we show that
various migrations can be obtained by varying the properties of the corona. A
new dynamo of Babcock-Leighton type also leads to the correct equatorward
migration by the non-linear relation between flux density and rise time of the
flux.
