This dissertation consists of two parts: research pertaining to the development of scalable pump techniques for gain guided index-antiguided fiber lasers and research relating to the development of passive athermalization schemes for solid state lasers. The first section primarily details the development of a side pump scheme that allows for power scaling of gain-guided index anti-guided fibers. While these fibers have been demonstrated in past research, none have used a pump technology capable of pumping with the efficiencies, uniformity, and necessary length to allow for scaling of the fiber lasers to high output powers. The side pumped scheme developed in this section demonstrates a 6 W output power fiber laser with room for improvement in efficiency and beam quality. The second section details work done on the development of technologies for passively athermalizing the output of solid state laser systems. Techniques for passively removing the dependence of laser output power/energy on the operating temperature of the laser system promise to reduce the weight, power consumption, and cost of fielded laser systems. Methods for achieving passive athermalization are discussed, as well as prior research in laser athermalization, background theory, enabling technologies, and experimental results. This work provides the basis for continued research of passive athermalization and the eventual demonstration of this technology.