In 2011, the Conference of Directors of National Libraries commissioned the authors to undertake an international survey of its membership: to establish the current state of legal deposit, or equivalent arrangements in all national libraries participating in the Conference of Directors of National Libraries including both the extent of legal deposit coverage and also how the deposited material may be used; and to identify any key lessons or principles which could be used for advocacy or to inform planning with regard to legal deposit. This paper reports the findings of that survey. The results confirm that e-legal deposit is now widespread at least for publications on CD-ROM and there is real traction towards securing e-legal deposit for web and electronic publications. However, it would appear that the terms of access to electronic publications under legal deposit are often more restrictive than for print or for original publication. Respondents also proposed a number of principles and advocacy points and these informed the development of an advocacy pack to be used by those national libraries seeking to secure the legal deposit of electronic publications. These advocacy points are reproduced in an Appendix to the paper.