The last two years has seen rapid development in the field of High Power Fiber Lasers. Reported output powers have dramatically increased by several orders of magnitude, from 10W to 1KW. While the generic benefits of fiber lasers are well known (e.g. efficiency and compactness) the long term reliability of system components needs to be proven before widespread deployment can occur. In this contribution, we address issues related to high power handling capabilities of fibre optical branching components. Monolithic, fused fiber devices are clearly the component of choice to enable fully integrated, reliable fiber lasers. The required components can be classed in two distinct groups. The first group are single mode devices whose function relies on cladding coupling based on fused viconical tapers and these include tap couplers, wavelength combiners/splitters, and filters. The second group includes multi-mode devices, primarily used for the power combining of multi-mode pump diodes. We describe the latest developments in state-of-the-art fused fiber components for fiber laser systems, including the use of low ratio tap couplers for optical feedback and control in fully integrated fiber laser systems of up to 100W, as well as polarization maintaining (PM) tap couplers and PM wavelength combination/splitting. We further describe the main issues relating to the practical manufacture and reliability performance of those devices for use in high power systems.