Abstract
One of the classic problems in operator algebra theory is the question whether every derivation from an algebra N into an N-bimodule J is automatically inner. In the present thesis, we study derivations with values into ideals of a semifinite von Neumann algebra M. Precisely, we characterize the symmetric ideals J of M such that every derivation from an
arbitrary C*-subalgebra (resp. von Neumann subalgebra) of M into J is automatically inner.