Abstract: The present invention relates to a system and a method for prediction and treatment of all kinds of slugs being formed in a flow line (20) system or wellbore tubing transporting a multiphase fluid towards a downstream process including a separator or a slug catcher at said process inlet. Said system comprises a slug detector (1) located downstream of the point for slug initiation and upstream of said process and a computer unit (4) integrated said flow line system and said downstream process including software which determines the type of the slug, its volume and predicts its arrival time into said downstream process. Said computer unit processes all its incoming data to obtain an optimum regulation of said process so that process perturbations due to incoming slugs are reduced to a minimum through said process.