Scale changes everything. The trend in the design and development of software-intensive systems today is toward scale that increases in every measurable way. Lines of code, complexity, dependency, communication, bandwidth, memory, datasets, and many other measures for our systems continue to reach and exceed the limits of our ability to produce high-quality systems for all purposes. Ultra Large Scale systems will be unbounded, integrating internet-scale resources. They will serve diverse stakeholders with competing objectives while being constrained by policy, regulation, and the behaviors of their users. The lines between development, acquisition, and operations will blur: ULS systems will not die; they will be too large to be replaced and will be inextricably connected to the day-to-day mission. Rather, they will continue to evolve over time with behavior often more emergent than planned. This workshop explores how to design, build, and evolve them.