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The demand for manufacturing of large parts is increasing, and widening to sectors traditionally based on the human workforce. Historically aeronautical and naval sectors have required capabilities for machining large parts, but new sectors like renewable energy power stations are demanding similar capacities, and also the pressure for productivity is forcing traditional sectors like civil construction to use procedures more typical of the industrial production. However, the academic research is far away from the requirements in this field. The reasons could be different. For instance: academia do not usually have access to the requirements of this niche industry where fast response engineering solutions are required to customize machines for making specific jobs. Furthermore, these machines are often one-off and industry try to "fix-it" without performing in-depth research, due to time and money limitations, since there is one/two-off systems. Another possible reason may be that the cross-sectorial topic does not particularly interest academia since there is limited ground for in-depth research. Finally, high level of investment required to have a large machine tool in the lab is another limiting factor. Therefore, most of the advances in the field of machine tools for large parts have been achieved by solutions proposed by the industry. Together with this situation, the need for large machines is increasing, and like the conventional ones, they should afford the continuous challenge of increasing the productivity and precision, so the need for high dynamics, when large travel ranges and heavy loads are involved. A proper foundation design and construction is the first difficulty, mainly because it is an issue not totally in the hands of the machine tool manufacturer. Although it could seem the opposite, the principles of precision design are near mandatory for the design of large machines guides and drives. Machine on machine configuration is a promising option to deal with large ranges and high dynamics. Operations like transport, handling, clamping and measuring large parts have a higher impact in the cycle time than in conventional size manufacturing. So, all these topics are a field where research and new solutions are demanded. Intelligent fixtures will be more and more used, machine self-calibration, part centring and in situ verification require from faster and cheaper techniques. Once the part is placed at its final position, far away from the workshop, the use of portable machines is increasing its importance. Their evolution comes from specific task machines to multi-task and flexible machines, easily reconfigurable. This evolution drives portable machines towards robotics, i.e. intelligent machines able to move autonomously and selfcalibrate over the part. There is a trend to produce just in situ, which is also affecting the whole factory towards the "container mini-factory", although that is not suitable for large parts. Finally metrology issues are a continuous source of challenges. Fast and traceable systems are required for sizes around 5-50 metres, being multilateration and photogrammetry the most promising technologies. Thermal deformations and the effect of heavy movable loads are the main source of uncertainty, so on-line self-calibration techniques are required.