Compressed Natural Gas (CNG) and biomethane when blended as a transport fuel (bio-CNG) have significant potential in Europe. However, this alternative fuel has not been developed in several European countries. One of the barriers to market penetration is the absence of a coherent regulatory framework to eliminate the disparity between European and national legislation. Using Ireland as a test case, this paper examines how conflicting policies can be aligned to ensure effective.bio-CNG market development. A key barrier is the regulatory ambiguity placed on transport fuel suppliers and investors who wish to connect to the network to supply bio-CNG. For example, the Irish 2002 Gas (Interim) (Regulation) Act states that all entities supplying natural gas from the network (including bio-CNG) must hold a supplier licence and are bound by the network code of operations. The obligations of the code act as a potential deterrent to bio-CNG suppliers due to the licencing complexity and associated costs. This paper critiques the current regulatory framework in Ireland, highlights areas of ambiguity and puts forward an aligned solution to allow bio-CNG market participants to utilise the network safely, in a regulatory sound and cost-effective manner. (C) 2016 Elsevier Ltd. All rights reserved.