A tuning device for an optical fiber grating includes a multi-part confinement member. The confinement member includes a feature such as a channel in which the fiber grating is disposed. Movement of the different parts of the confinement member relative to one another causes compression or tension of the fiber grating. The confinement member may include first and second slides. One end of the fiber is bonded to the first slide, the other end of the fiber is bonded to the second slide. The grating section of the fiber is confined in a channel formed by adjacent surfaces of the slides. The dimensions of the channel are selected such that the fiber grating is maintained in a relatively straight orientation without buckling when compression strain is applied to the fiber. An actuator may be employed to control the strain applied to the fiber, i.e., to axially compress or stretch the fiber grating by driving one or both of the slides in a controlled manner. The resonance wavelength of the fiber grating can be tuned as a function of the strain applied to the fiber. The confinement member may alternatively include deformable slides which axially deform, i.e., extend and retract so as to change in length. Each end of the fiber is affixed to both of the deformable slides so that axial compression or stretching of the fiber grating is achieved through deformation of the deformable slides. The fiber grating tuning device can be deployed in components such as tunable fiber lasers and tunable fiber filters.