The EURO Working Group on Operational Research Applied to Health Services (ORAHS) was formed in 1975 as part of a programme for developing special interest groups within the European branch, EURO, of the International Federation of Operational Research Societies (IFORS). ORAHS provides a network for researchers involved in the application of systematic and quantitative analysis in support of planning and management in the health services sector. The group has at present members from 22 countries, mainly in Europe but also from other countries such as the U.S., Canada and Australia (http://orahs.di.unito.it).

Traditionally, the group meets every summer, for one week, in a different European host country (and occasionally outside of Europe). Along with the scientific programme, a field trip to a local healthcare facility is typically arranged to provide an opportunity for delegates to appreciate local health services and to facilitate a discussion with medical personnel and health planners.

In July 2011, the ORAHS conference was held in Cardiff, the capital city of Wales (www.orahs2011.com). There were 120 scientific delegates, 81 talks and 17 posters presented. The conference was a great success with a range of stimulating talks, an insightful field trip, a varied social programme and sunshine all week (an unusual feature for a Welsh Summer!). We were members of the organising committee and were delighted to be asked by the editors of Health Systems to act as guest editors for this special issue, the first call being announced during the conference. A number of papers were submitted for consideration, with seven papers finally making it through the comprehensive reviewing process and appearing in this issue.

The underpinning ethos of Health Systems is that all aspects of health and healthcare delivery can be viewed from a systems perspective. We feel we have achieved this with papers exploring various systems ranging from the emergency department, transplant waiting lists, geriatric care and tertiary care. We trust this collection of papers will both raise awareness of OR modelling to those from other disciplines, and facilitate an exchange of ideas about how OR can be interfaced with techniques drawn from related fields to meet wider health system challenges through a multi-disciplinary approach.

The first paper in this special issue considers the strategic management of the emergency department, an important factor in any healthcare system. Mould et al. present findings from the redesign of an emergency department in Scotland, which utilises aspects of systems modelling and discrete event simulation. It is particularly impressive that this work incorporates a discussion of the difficulties of evaluating the impact of individual changes within complex systems and the mention of gaming.

In today's world, it is increasingly important to make efficient use of vital but expensive resources. Such an area where this is paramount is in the scheduling of surgical units. In Holm et al.'s paper some very interesting and practical findings are obtained from a case study at the Akershus University Hospital in Norway. The novelty of this paper is in the multi-methodology approach linking ‘soft OR’ (soft systems methodology) and ‘hard OR’ (discrete event simulation). As noted by one of the reviewers: ‘[…] this is likely to yield a substantial contribution to multi-methodological thinking’.

The third paper, by Gallivan and Crowe, looks at another issue of high importance: transplant waiting lists. The discussion in this paper revolves around the subject of paediatric care but the methodology could very well be applied to other types of transplant lists. The approach models the waiting list as a Markov chain and there is an interesting connection made to higher level geometry once again showing the subtle connections ever present between pure mathematics and OR.

The challenge of dealing with an ageing population with multiple healthcare needs is one facing many countries. The next paper, by McQuillan et al., combines Bayesian Networks and Coxian phase type distributions to provide better models for predicting the length of stay of geriatric patients. This is an important performance measure used in modelling to estimate future healthcare needs.

In our fifth paper, Rowse et al. take us outside of the hospital and consider workforce planning in primary care. This paper fills a gap in the literature, with a case study on optimisation of skill-mix within nurses’ grades in the district nursing service. The modelling approach utilises both simulation and linear programming. It is clearly directed to aiding a better provision of care for those patients in the community. This is of increasing importance as more countries move to reduce care taking place in a hospital bed, combined with the healthcare challenges presented by an ageing population.

The paper by Hindle et al employs geographical modelling to estimate the patient episode flow effects between geographical areas and hospitals. The context and associated challenges are clearly described in this paper and is very relevant to the scope of this special issue. This work uses a region of Northern Ireland as a case study; however, the methods and conclusions are applicable to most healthcare regions.

Last but by no means least, the paper by Mustafee et al. has a particular place in the wider body of healthcare research. Firstly, the paper makes use of a growing technique in popularity, agent-based simulation, and secondly, the work does not directly consider patients but clinical products. Cutting and packing heuristics are combined with agent-based modelling to consider the problem of transporting clinical goods. The cross contamination of these products is an important issue and the consideration given in this paper is a very welcome conclusion to the special issue.

We would like to thank all the authors for submitting such high-quality papers to this special issue, and we commend them for their work. Collectively, these papers provide the reader with a range of OR methodologies together with a high emphasis on application and impact. Correspondingly we feel that this special issue would not just be of interest to researchers, but also to practitioners working in the health service.

As guest editors, we would also like to take this opportunity to express our sincere gratitude to the many reviewers who all did a superb job critically analysing each piece of work in a timely manner. We are also extremely grateful to the editors of Health Systems for permitting this opportunity to guest edit the first ever special issue to appear in the journal, and for their helpful advice along the way. We hope that they are as happy with the final product as we are and that you, the reader, will enjoy it too.