For the last ten years, anthropologists have been studying work, family and technology in Silicon Valley. Using intensive observation and ethnographic interviews, we have investigated the daily life of people in Silicon Valley in an ecosystem of research endeavours we have dubbed the Silicon Valley Cultures Project, supported by grants by the National Science Foundation and the Alfred P. Sloan Foundation, as well as through partnerships with the Institute for the Future. The latter collaborated to conduct ethnographic interviews on the details of work and technologically mediated communications in Bangalore, India, Dublin, Ireland, and the Taipei-Hsinchu corridor in Taiwan, revealing the complexities of global interconnections in families and workplaces. These projects have explored the penetration of work, technology and global interconnections into the daily lives of the people. We used a comparative approach, a multisite research design, to yield different research questions. Cross-site analysis allows us to see that differing social and technical infrastructures shape the way trust is built and maintained. Locating research sites in different locations also emphasizes the problematic nature of technologically-mediated relationships, since networks built at a distance and maintained virtually have risks that locally constructed networks do not. Workers in Silicon places are simultaneously inwardly-focused and embedded in a local context and connected to global economic and communications nodes. Interdependent high-tech work, often using technologically-mediated communication, requires a high degree of trust. The cultural construction of 'trust', and the culturally situated negotiation of trust relationships need to be explored in this context. High-tech knowledge work is done by networks of interdependent global workers that must share information, act under a severe time constraint, and establish effective relationships at a distance. The management of interpersonal and organizational expectations that is embodied in the concept 'trust' is an example of how locally constructed cultural realities are enacted on a global stage.