The present invention relates to an adjustable trajectory guide having a guide portion adapted to hold or provide a guiding for a medical instrument along a defined trajectory, and at least one adjustment section comprising: at least one elongated flexible beam member connected at its first end to the guide portion, and having at its second end a first engagement interface adapted to provide a connection to a support structure holding the trajectory guide at least one second engagement interface which is movable relative to the at least one beam member and which is adapted to provide a connection to an actuator, at least one coupling member coupling the first end of the beam member to the second engagement interface, wherein the coupling member is capable of transmitting force and/or torque from the second engagement interface to the first end of the beam member. The present Invention further relates to a trajectory guide adjustment system comprising such trajectory guide, and corresponding method for aligning an elongated medical instrument utilizing such trajectory guide adjustment system.