Trends and opportunities in light source development

After a decade of rather quiet growth for FELs there is now a lot of activity in the light-source community. This is the result of a combination of factors including successful operation of the third-generation light sources, the establishment of a very productive user community at both synchrotrons and FELs, and the continuing technical improvements of accelerators and related technology which allow even more challenging machines to be considered. There are a number of themes that carry this development including pushing wavelengths shorter, brightnesses higher, pulses shorter, increasing average power, and providing for multiple synchronized photon beams with multiple wavelengths. This talk will discuss some of the plans and proposals currently circulating and attempt to provide a glimpse into the near future of our field by illustrating the technologies that drive source development.