  A new mechanism for the evolution of primordial magnetic fields is described
and analysed. The field evolution is followed from the time of its creation
until the epoch of structure and galaxy formation. The mechanism takes into
account the turbulent behaviour of the early universe plasma, whose properties
determine strongly the evolution of the field configuration. A number of other
related issues such as the case of an electroweak plasma are also considered.
Finally, as an example, the mechanism is applied to specific models.
