Fiber Bragg Gratings (FBG) are often used in telecommunications applications involving dense wavelength division multiplexing (DWDM) and Optical Add-Drop Modules (OADM). Other FBG applications include wavelength stabilization, dispersion compensation and gain flattening. In comparison to popular thin film filters, FBG based devices promise to deliver the steep-skirted profiles necessary to provide high adjacent channel isolation as the channel spacing in DWDM systems gets smaller and smaller. The in-fiber solution of the FBG is also advantageous to system designers striving to reduce their network's overall insertion loss. In DWDM applications even minimal wavelength shifts can cause loss of data. In an uncompensated package, the center wavelength of a Fiber Bragg grating typically shifts 0.01 nm per 1 degree centigrade. Hence in 50 GHz (0.4nm) DWDM systems, a few degrees of temperature shift can dramatically affect system integrity.