Health and Social Care in the Community 9(4), 215 – 227 © 2001 Blackwell Science Ltd 215 Abstract Despite the growing literature that collaboration is a ‘good’ thing, there are calls emphasising the need for evidence of its effectiveness. However, the nature of the evidence to assess effectiveness is less clear. This paper examines the components that contribute to the challenges that confront evidence on collaboration. It considers the differing interpretations that have been placed on evaluation and explores how ways of determining the outcomes of collaboration and the levels of outcome measurement to assess collaborative effectiveness are influenced by the multifactorial nature of the concept. Evidence on the impact of collaboration is influenced by the diversity of perspectives and conceptual facets, and difficulty in measurement of the notions involved. Other factors discussed are the choice of macro or micro evaluation, of proximal or distal indicators, of short and long-term effects, or of individual-level or collective community-level outcomes. The suitability of randomised controlled trials for the measurement of collaborative outcomes as well as the requirement of mixed methods evaluations are highlighted. An evaluation of five community partnerships in South Africa is employed as an example to link the evaluation concepts that are discussed to a real enquiry. If collaboration is to be successful in making a difference in the lives of people, then increasing the precision and context of appraising its effectiveness will reduce the nature of inconclusive evidence and is likely to improve the practice of partnerships, coalitions and joint working in health and social care. Keywords: collaboration, evaluation, evidence-base, health and social care, methodology, partnerships Accepted for publication 6 March 2001 Blackwell Science, Ltd Collaboration and partnerships: developing the evidence base Walid El Ansari 1 , Ceri J. Phillips 2 and Marilyn Hammick 1 1 School of Health Care, Oxford Brookes University, UK and 2 School of Health Science, University of Wales Swansea, UK Correspondence Walid El Ansari Senior Lecturer in Public Health & Epidemiology Public and Community Health Department School of Health Care Oxford Brookes University Heritage Gate Sandringham House Sandy Lane Oxford OX4 6LB UK E-mail: walid.ansari@brookes.ac.uk Note For the purpose of this paper, the terms collaboration, partnership, coalition and joint-working are used inter- changeably. Although some distinctions are made in the literature, in this report, these terms are used to refer to the notion of collective actions by individuals or their organisations for a more shared communal benefit than each could accomplish as an individual player. Introduction Numerous recent reports advocate the concept of collaboration within the context of health and welfare services and professional education for healthcare practitioners. The shift is from separatism between services and patronage on the part of the professionals to a partnership model (Statham 2000). In the UK, improved teamwork between professionals is strongly recommended in recent health service publications, e.g. Department of Health (1998). Local partnerships between health service and universities, with a strategic commitment to achieve the tripartite mission of service, teaching and research, have been suggested (Nuffield Trust Working Group on NHS/University Relations 2000). Changes in education and training are funda- mental to these arrangements and calls for programmes that are genuinely multiprofessional are currently linked