About the Centre for Drug Research

The Centre for Drug Research, (CEDRO), was established in 1996 as a department of the School of Environmental Sciences (Faculteit der Ruimtelijke Wetenschappen), at the University of Amsterdam. Drug  research activities directed by Peter Cohen existed already since 1983 and culminated only later in an organizational unit called CEDRO. The Centre's research efforts relied mainly on outside funding in spite of the fact that the University has always been willing to pay for a small part, thereby helping its continuity. Due to the sound reputation of its researchers as well as the special position held by Amsterdam and the Netherlands in the field of international drug research, CEDRO has gained much esteem in the scientific community.

In 2000, CEDRO moved to the SCO Kohnstamm Institute in the then newly formed School of Social and Behavioral Science, where it remained till December 2003. Per January 2004 CEDRO stopped being an institute acquiring research funding from third parties. CEDRO lives on as a virtual entity to maintain her website on which all CEDRO research and much more is published. New publications from the old CEDRO staff will be published there as well.

CEDRO's director, dr Peter Cohen, retired from the university per March 1, 2004. Since his retirement he continued publishing, copies of which can be found on the site.

CEDRO: a brief history

CEDRO indirectly came forth from the ‘drug research program’, ('onderzoeksprogramma drugsbeleid') requested in 1983 by the Municipality of Amsterdam. This program was started at the now defunct Instituut voor de Wetenschap der Andragogie (IWA), at the University of Amsterdam, and lasted until 1988. It was initiated with funding by the City of Amsterdam but partly financed as well by the former Ministry of WVC, (Ministry of Welfare, Public Health and Cultural Affairs), the Home Office, The Ministry of Justice and the Prevention Fund. The program incorporated a manifold of socio-scientific research disciplines, such as: psychology, criminology, human geography, anthropology, and medical sociology. Two researchers from the Faculty of Law carried out a part-time study of the Amsterdam drug market. The study of 'non-deviant' cocaine use, conducted at the School of Environmental Sciences, was also a part of this  Municipality based research project. The population studies which used to be such an important part of the research portfolio, started at the same time with a drug use prevalence study among the population of Amsterdam, 12 years and over.

After the completion of the research project at the IWA in 1988, Cohen and the co-ordination of the drug research program was moved to the Department of Human Geography at the School of Environmental Sciences. Other disciplines remained involved in the Cedro drug research.Drug research is carried out at other faculties too, notably at the Department of Criminology, the Faculty of Law and at the Faculty of Medicine.

In addition to these different projects, two other major studies were carried out at the Department of Human Geography: a cocaine use study of  'non-deviant' drug users (with a follow up study) and a study on the use of licit and illicit drugs among the adult population of Amsterdam. The cocaine research project resulted in three publications and in repeat studies in Belgium and the UK by local investigators.

Population drug use research became one of the main pillars of the group that later became CEDRO. Since 1987, large local surveys on the use of licit and illicit drugs among the population of Amsterdam were carried out every three years. For this purpose, for each survey, approximately 4,000 citizens (>12yrs) randomly picked from the Amsterdam registry of inhabitants participated in detailed interviews relating to the use of substances and its frequency. Due to the high sampling quality, magnitude, continuity and uniformity, these studies meanwhile are considered very reliable population surveys on the use of substances.

In the nineties, drug research at CEDRO entered an international phase. In connection with the preparations of the 'Drugsnota' of the Government, the Ministry of VWS, (Ministry of Health, Welfare and Sports), CEDRO designed comparative research of cannabis policies. For the Ministers involved, as well as the Government, this study, with its detailed information on cannabis policies in Germany, France and the USA, served as a tool, with which their own policy could be placed into perspective. In order to conduct this study, close co-operation with the Institute for Drug Research in Bremen, (Bremer Institut für Drogenforschung), at the University of Bremen, and the Center for Drug and Alcohol Studies at the University of Delaware, took place.

Cooperation with the University of California (Santa Cruz) helped execute the study that compared cannabis use careers and use patterns in San Francisco, Amsterdam and Bremen (published in 2002). Plans for cooperation with the Institute for Special Populations Research National Development and Research Institutes (NDRI) in New York were developed as well. Focus should be on comparing CEDRO data on initiation of use between the USA and the Netherlands. NDRI wanted to look into the combined use of tobacco and cannabis. However both plans never materialised because of lack of funding. Still cross national comparative research is probably the most important innovation for drug use research for the next decades.

CEDRO also did not realize funding for its plans to compare the cannabis growing and distribution situations of Amsterdam and the frontier town Venlo (near Germany). This meant that the CEDRO research structure could not survive, although its widely used website will continue to be open to the public. Peter Cohen will stay another few years to maintain the website and collaborate with collegues in different Universities to develop theory around the construction of the modern age concept of 'addiction'.


The criminalization of drug use and its perception by society as 'major deviance', are important determinants in the way drug use occurs. The use of illegal drugs is 'regulated' almost entirely via formal criminal law mechanisms. Of course informal regulatory mechanism are as important (or more..). The interpretation of drug use is virtually left up to medical perspectives alone.

CEDRO has always had a distinct socio-scientific orientation and regarded drug use as natural human behaviour, primarily shaped by contextual and social variables. This is an important difference to the more common interpretation with a preponderantly criminal or medical orientation. Criminalization and the depiction of drug use as pathological behaviour have led to serious shortcomings in the attainment of knowledge in this field, (notably theory). These shortcomings stand in the way of rational policy-making.

Amsterdam as experimental garden

As far as drug use and drug policy are concerned, the Netherlands, and Amsterdam in particular, hold a leading position in the world. Since drug policy is less repressive, drug use manifests itself more openly than elsewhere. Therefore, more than in other cities or countries, possibilities for conducting relevant, new empirical research in Amsterdam, exist.

Because views on drug use are so strongly dominated by tight, almost dogmatic prejudice, the need for systematic empirical research on drug use outside of the classic prison/hospital context, has hardly arisen in the past. With the slow realisation that the majority of drug use takes place outside of this context, the relatively easy access to Amsterdam's drug users provides an important advantage in setting up new research.


The Centre for Drug Research had the following goals:

  1. Conducting socio-scientific research in the fields of drug use, drug policy and drug distribution, on a high methodological and theoretical level.

  2. Developing expertise, theories and research techniques for the diverse facets of the drug problem in a way, which will lead to a more scientific understanding of the entire drug research field.

  3. Dissemination of knowledge on the complexity of the drug problem through publications, readings, (guest-)lectures and consulting among social scientists, lawyers, and policy-makers.

  4. Contributing in the promotion of international exchange of research findings and international co-operation in drug research, via existing international network contacts.

The CEDRO Internet Site

An important task of CEDRO consists in providing interested parties with research findings. In view of the international attention attracted by the drug situation in the Netherlands and the international character of some of the studies, CEDRO has decided to display a large portion of its research findings on the Internet.

In the autumn of 1994 when only a few hundred websites existed world wide, CEDRO opened its own site on the Internet. The website has since evolved into the second largest drug research site in Europe. Though the Internet offers a large amount of drug-related information, there is a great demand for scientific and systematically arranged information. Every day, 700 to 800 people visit the site. On average, per month 41,000 documents are retrieved from the CEDRO website. The most important sections of the website are the on-line library and the statistics section.

The extensive on-line library contains most of the journal articles, papers, and research reports written by the CEDRO staff. Most of the documents are in English, some of them are in Dutch, and in many cases CEDRO has chosen to provide German, Italian, French, Korean and Russian translations for our international audience. In fact, CEDRO was the first organisation in The Netherlands that published Russian texts on the internet using the Cyrillic alphabet. In many cases, large documents are also offered in Adobe's PDF format for off-line printing and reading.

CEDRO uses the internet site and its connected electronic mailing list as tool for achieving the largest possible dissemination of research findings. The URL of the website is: http://www.cedro-uva.org/


In fall 2003 it was decided that CEDRO would terminate its costly research activities because of increasing problems of acquiring funding for the problems it considered relevant. The website and some literature study will be continued.