Equilibria and evolutions in the coronal magnetic configurations due to the interactions among active regions are investigated. The magnetic structure includes a current-carrying flux rope that is used to model the prominence or filament. We use either two dipoles or four monopoles on the boundary surface to model active regions, and the change in the boundary conditions corresponds to either the horizontal motion of magnetic sources or decaying of the active regions. Both cases show the catastrophic behavior in the system's evolutions. The results have important observational consequences: most eruptive prominences that give rise to CMEs are driven by the interactions between two or more active regions. Such eruptions may not necessarily take place in the growing phase of the active regions, instead they usually occur at the decay phase.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service.html