When the Popular Unity's candidate Salvador Allende came to power in 1971, he nationalized Chile's banks and industries, and the international corporate-political community responded, with US President Richard Nixon ordering the CIA to ‘make the [Chilean] economy scream’ (p. 45). Foreign aid plummeted and foreign credit shrivelled, but Allende pressed on. Seeing science and technology as political instruments to shape Chile's socialist future, President Allende authorized his technical director of companies and trade, Fernando Flores, to commission British cybernetician Stafford Beer to design a computerized network linking factories and government management to monitor production and distribution, identify problems from the bottom up, and respond to needs in ‘real time’. This became Project Cybersyn (Proyecto Synco). The Chilean and British designers are Eden Medina's ‘cybernetic revolutionaries’.

Medina begins her technological, political, economic and cultural study of Project Cybersyn by providing context and a fuller history of the computerization of Chile, beginning in the 1960s. She then pieces together the story of what may be cybernetics’ most ambitious endeavour, using it to explore if and how political goals might be embedded in a technological design, in this case the creation of a high-tech ‘people's science’ that would strengthen communication between labour and management. ‘At stake’, she writes, ‘was the design of a computer system that would not only facilitate production in an economy in crisis but instantiate the Chilean vision of socialist democracy’ (p. 69).

As for Stafford Beer, we learn, he ecstatically took on this task. Having spent years as a business management consultant, here was an opportunity to apply his ideas of the corporation as a nervous system to a national economy. (Beer published Brain of the Firm in 1972.) Beer based Project Cybersyn on his viable system model (VSM), or liberty machine, with the first level being the sensory input (the workers), then moving up to the cerebral cortex – that is, the highest-level management teams who would resolve the most complex problems from the capital, Santiago. After providing a history of Beer's career and a detailed description of VSM, Medina turns to Project Cybersyn's four major components: Cyberstride, CHECO, Cybernet and the Opsroom.

With her analysis of Cyberstride, the program software, and the Chilean Economic simulator (CHECO), the systems for building models and predicting trends, Medina delves into the story of cross-cultural tech transfer between British programmers and Chilean designers. Medina's analysis of Cybernet, the hardware ‘internet’, continues to explore technological, political and transnational aspects affecting Cybersyn's full realization. The government owned only four mainframes and expansion would be difficult since manufacturers – IBM and Burroughs – had abandoned Chile upon Allende's election. Beer was given time on only one of these machines for Project Cybersyn. As for the Cybernet's nodes, the designers made do with what was available: a few hundred outdated telex machines connected factories up and down the coast to the computer in Santiago.

Medina's description of the high-tech Opsroom (operations room), where information was to be gathered and analysed and decisions were to be made, provides a valuable historical example of how industrial and graphic design can be engaged to articulate technological and political values; that is, to provide the ‘image’. The hexagonal Opsroom, imagined as cybernetic socialist modernism, was to have a wall for electronic panels showing algedonic signals, Beer's homeostatic device for tracking production trends and the level of a problem's urgency. There were to be screens displaying data as modern graphs and flow diagrams. Control panels were to be built into the armrests of fibreglass swivel chairs and participants would have sat in a non-hierarchial circle. Yet this futuristic plan lacked access to the latest electronics and up-to-date information. Plus, women seemed left out of the design.

Pointing to how certain traditional ideas of class and gender were retained, Medina notes that large buttons on the Opsroom consoles were intended to accommodate workers’ hands, while Beer forbade keyboards so as to ‘eliminate the girl [typist] between themselves and the machinery’ (p. 127). Cybersyn intended to establish worker–supervisor–government overseer communication, but even at the research stages, Medina reports, information-gathering engineers dispatched to factories ignored workers, interacting only with supervisors. Beer intended the communication system to allow for more decision-making input by labour, yet the Chilean right claimed that ‘Popular Unity Controls Us by Computer’ (p. 185) and Beer's leftist colleagues (the British Society for Social Responsibility in Science) snidely reported, ‘Chile: Everything under Control’ (p. 191). Cold War pressures made socialism a wide target and Project Cybersyn was seen as ‘Big Brother’, exploiting the oppressive potential of cybernetic ‘command and control’. Medina's detailed attention to internal and external stresses and judgements of the project is impressive. She also covers complex relationships between key figures, such as Flores's distancing himself from the project, as he took on the burden of the expanding threats of counterrevolution.

Project Cybersyn was never fully implemented. In 1972, however, it effectively helped to put down a crisis when a strike by truck owners and most of the professional class nearly paralysed the country and toppled Allende's regime. Medina offers a fascinating chapter on how the internet of telexes successfully transmitted information (reportedly two thousand messages a day) in near real time, allowing the government to keep goods and fuel moving. Here was evidence of Project Cybersyn's potential. But we know how the story ends. On 11 September 1973 General Augusto Pinochet's military forces storm the presidential palace. Allende dies. Project Cybersyn is abandoned.

In the epilogue, Medina tracks the whereabouts over the last thirty-five years of Project Cybersyn's main actors caught initially in Pinochet's dictatorship. Flores was imprisoned, would later lose interest in cybernetics, and then settled in Silicon Valley. Others end up in the UK, at Imperial College, for example. Beer, we read, ‘worked tirelessly to get his friends out of Chile’ and ‘kept up these efforts until 1976, when the Pinochet government finally released Fernando Flores into exile (p. 225). The epigraph Medina chose for her prologue is taken from Beer's own assessment of Project Cybersyn in 1972: ‘One day this will make quite a story’ (p. 1). Indeed. With Cybernetic Revolutionaries, Eden Medina has provided a compelling analysis of an important chapter in the global history of cybernetics, one linking northern and southern hemispheres, and one that coincided with great political hope, then tragedy.