Many of the problems facing governments have a scientific dimension to them. Policy makers often do not give sufficient weight to considering the views of scientists on these matters. Over the past decade or so, Sri Lanka has encountered a number of controversial issues of high public concern such as, the connection between usage of agricultural chemicals and chronic kidney disease of unknown origin, the influence of a local industry on the quality of water in Rathupaswala and the occurrence of Dicyandiamide in imported milk powder. In each of these cases, insufficient attention was paid to the scientific evidence available as well as the evidence that could have been generated by scientific inquiry, pertaining to these issues. Policy making of course, cannot be based only on consideration of scientific evidence, if not for any other reason but for the fact that the scientific evidence to support a particular viewpoint on a controversial issue is rarely unequivocal. Even in the case where there is very strong evidence to support a particular viewpoint, the policy makers will consider many other factors such as public opinion, political ideology and the perceived priority of immediate versus long term effects of any particular action. However, any policy which totally ignores the “irreducible and stubborn facts” generated by scientific inquiry, has a poor chance of producing overall benefit to the community in the long run. This raises the question of what scientists can do to influence policy making. Should scientists get involved in politics? The cultures of science and politics are different from each other, and do not mix. In politics the pursuit of power is paramount, while science is driven by the search for truth. Scientists who move directly into politics quickly lose the respect of their peers as scientists. On the other hand, direct advocacy by individual scientists have been rarely successful in influencing policy and have been susceptible to accusations of partiality by those holding contrary views. In this context, the professional associations and other scientific bodies, play an important role in pro-actively providing the public and policy makers of scientific information that will be accepted as being credible and unbiased, on controversial issues of high public concern. A notable and isolated example of such activity was the issuance of two reports on the Eppawala phosphate deposit, one by the National Academy of Sciences of Sri Lanka in 1998, and the other by the National Science Foundation in 1999, both of which weighed heavily on the decision by the courts in the year 2000, not to permit the signing of an agreement granting mining rights to a foreign company. Such pro-active efforts will also go a long way to change the perception of scientists as persons living in ivory towers unconcerned with society, while at the same time preserving the essential dignity of the scientific enterprise.