Fibring is recognized as one of the main mechanisms in combining logics, with great significance
in the theory and applications of mathematical logic. However, an open challenge to fibring is
posed by the collapsing problem: even when no symbols are shared, certain combinations of logics simply
collapse to one of them, indicating that fibring imposes unwanted interconnections between the given
logics. Modulated fibring allows a finer control of the combination, solving the collapsing problem both
at the semantic and deductive levels. Main properties like soundness and completeness are shown to be
preserved, comparison with fibring is discussed, and some important classes of examples are analyzed with
respect to the collapsing problem.