not. The following four types of similar globally distributed configurations are not FTS: Global knowledge work is defined as geographically dispersed knowledge workers working collaboratively from multiple locations. This is not FTS because there are no handoffs. 24/7 service. In this configuration work is distributed to workers who are available at that time. It is focused on availability and the workers have little dependency, whereas FTS is focused on duration reductions and requires dependencies between the different sites in order to perform the daily handoffs. 24-hour manufacturing. This configuration focuses on making shifts fully optimize expensive resources that could not produce more by increasing the number of employees per shift. However, this driver of reducing the resource cost is not the driver of FTS. Collocated multi shifts. In contrast to FTS this configuration chooses one location where labor is cheap and runs multiple eight-hour shifts concurrently. Difficulties FTS's largest strength, spreading the development over multiple time zones, is simultaneously its largest weakness. Its distributed workflow is more complex to implement due to cultural and technical differences as well as the differences in time making coordination and communication challenging. The main reason why FTS is difficult to implement is because the handoffs are an essential element that is hard to get right. The largest factor causing this difficulty is poor communication. There are few documented cases of companies successfully applying FTS. Some companies have claimed to successfully implement FTS but these companies did not practice the daily handoffs. However, a limited amount of successful applications of FTS that did include daily handoffs of artefacts, using a distributed-concurrent model, were found by Cameron. Recent studies on FTS have moved to mathematical modeling of FTS. The research is focused on the issue of speed and the issues around the handoffs. Methods As FTS is a sub-field of GDSE, the same agile software development methodologies that are found to work well in GDSE work well with FTS. In particular, Carmel et al. (2009) argue that agile software development methodologies assist the FTS principles because they: support daily handoffs. The continuous integration and automated integration of source code allows each site to work in their own code bases during their work day, while the integration maintains updated, testable code to be used by the next site. deal with communication. Agile methodologies emphasize communication. They specifically emphasize face-to-face communication, which can be done within one site.