Quantifier elimination for henselian fields relative to additive and multiplicative congruences

Several classes of henselian valued fields admit quantifier elimination relative to structures which reflect the additive and multiplicative congruences of the field. Value groups and residue fields may be viewed as reduts of these structures. A general theorem is given using the theory of tame extensions of henselian fields. Special cases like the case ofp-adically closed fields and the case of henselian fields of residue characteristic 0 are discussed. This work was completed during a visit in the Institute for Advanced Studies at the Hebrew University of Jerusalem.