This issue of Physiological Measurement follows the successful 9th International Conference on Electrical Impedance Tomography. It was hosted by the Thayer School of Engineering at Dartmouth College, co-organized by Alex Hartov of Dartmouth and Eung Je Woo of Kyung Hee University, and generously funded by the Impedance Imaging Research Centre (IIRC) in Seoul.

The conference provided a platform for researchers in all aspects of electrical impedance tomography (EIT) to engage in common areas of interest, whilst also giving the opportunity for the community to broaden its outlook in the areas of clinical applications and new technologies associated with EIT. This upholds the tradition of previous successful conferences on biomedical applications of EIT, as with the jointly-organized 8th Conference on Electrical Impedance Tomography, which was co-organized by the Impedance Imaging Research Centre (IIRC) in Seoul and the Austrian Society for Biomedical Engineering (ÖGBMT). The next conference is due to take place in Manchester in the UK and has already attracted a large number of abstracts.

This issue contains papers stemming from discussions and feedback during the conference on EIT research areas. The conference was also an opportunity for new researchers to join the community and propose recent innovations. There were 57 papers presented at the conference, and all authors were invited to prepare new peer-reviewed papers for inclusion in this issue of Physiological Measurement. The manuscripts were put through a careful review process before selection. A total of 14 were accepted covering an important range of topics including hardware, algorithms, new technologies including non-contacting methods, and clinical applications.

The papers included in this issue clearly reflect the continuing interest in EIT. New developments and trends are visible, such as non-contact methods using magnetic fields, MREIT (bringing together EIT and magnetic resonance imaging), magnetic induction tomography (MIT), clinical applications, new hardware and algorithms. The presentations in these new technologies continue to grow and it will be interesting to see how they contribute to future clinical applications. Clinical applications were strongly represented at this year's conference. These included brain function, breast imaging, the thorax, and a new target, the prostate. It is important that researchers do not neglect the challenges that clinical applications of bio-impedance and EIT present, as there are still many technical difficulties that need to be overcome in order to provide valuable clinical tools. However there are promising signs that many are close to realization.

EIT therefore continues to provide researchers with new challenges. The high quality of the research papers in this special issue is clear evidence of significant advances in the field.