The European Science foundation (ESF) has produced a policy paper recommending that studies of stem cells from embryos and adults and therapeutic cloning, but not reproductive cloning. The paper lists ten recommendations, in which it seeks to address both scientific and ethical concerns. 'As scientific knowledge about human stem cells is at an early stage, it is recommended that, at this time, it is essential to permit studies of stem cells from embryos, foetal tissues and adults to determine the potential of the different types of cells,' writes Enric Banda, Secretary General of the ESF. He adds however that the enactment of legislation to ensure that such research is properly regulated and controlled is vital. The paper describes the differences in legislation between countries as a 'cause of concern', and recommends that 'appropriate measures are put in place as soon as possible'. The recommendations add that, 'when therapies from the study of human stem cells become available, patients from all countries will wish to use these results. The ESF recommends that, in developing their legislative framework for this type of research, European countries take this reality into consideration.' The study of chimaeric embryos, embryos created by the fusion of a nucleus from on mammalian species with an oocyte from another species should be limited to non-human species which it can be ethically justified, such as in the case of endangered species, recommends the ESF. Addressing the issue of funding, the ESF emphasises that adequate funds must be made available from public bodies to the scientific community outside the commercial sector so as to keep pace with developments in the commercial sector. Finally, the ESF recognises that regulation and legislation will need to be kept under continual review on account of scientific advance. The ESF pledges to ensure that the paper is regularly updated in order to reflect scientific and regulatory changes.