A globally applicable code of conduct specifically dedicated to biosecurity has been developed together with guidance for its procedural implementation. This is to address the regulations governing potential dual-use of biological materials, associated information and technologies, and reduce the potential for their malicious use. Scientists researching and exchanging micro-organisms have a responsibility to prevent misuse of the inherently dangerous ones, that is, those possessing characters such as pathogenicity or toxin production. The code of conduct presented here is based on best practice principles for scientists and their institutions working with biological resources with a specific focus on micro-organisms. It aims to raise awareness of regulatory needs and to protect researchers, their facilities and stakeholders. It reflects global activities in this area in response to legislation such as that in the USA, the PATRIOT Act of 2001, Uniting and Strengthening America by Providing Appropriate Tools Required to Intercept and Obstruct Terrorism Act of 2001; the Anti-Terrorism Crime and Security Act 2001 and subsequent amendments in the UK; the EU Dual-Use Regulation; and the recommendations of the Organization for Economic Co-operation and Development (OECD), under their Biological Resource Centre (BRC) Initiative at the beginning of the millennium (OECD, 2001). Two project consortia with international partners came together with experts in the field to draw up a Code of Conduct on Biosecurity for BRCs to ensure that culture collections and microbiologists in general worked in a way that met the requirements of such legislation. A BRC is the modern day culture collection that adds value to its holdings and implements common best practice in the collection and supply of strains for research and development. This code of conduct specifically addresses the work of public service culture collections and describes the issues of importance and the controls or practices that should be in place. However, these best practices are equally applicable to all other microbiology laboratories holding, using and sharing microbial resources. The code was introduced to the Seventh Review Conference to the Biological and Toxin Weapons Convention (BTWC), United Nations, Geneva, 2011; the delegates to the States’ parties recommended that this code of conduct be broadly applied in the life sciences and disseminated amongst microbiologists, hence the publishing of it here along with practical implementation guidance. This paper considers the regulatory and working environment for microbiology, defines responsibilities and provides practical advice on the implementation of best practice in handling the organism itself, associated data and technical know-how.