The principles and practices of design using geosynthetic barriers take into account a number of different parameters considered by professionals engaged in the process. The design guide aims to assist the process by identifying the various characteristics of barrier types and comparing them with the requirements of a variety of different applications. The document has been developed as part of the ISO project “Design using geosynthetics” which offers design advice to professionals involved in the design of civil engineering and construction solutions using geosynthetics materials. Overall the intent is to encourage appropriate selection of materials and design methods to suit particular applications, rather than to redesign projects to suit predetermined materials. Many aspects of the design process have been considered, as well as the particular parameters of various sites and applications. The development has followed the ISO process of development via a committee of international experts over a period of 24 months and with presentations at various international conferences to ensure buy in from the international community. This paper will describe both the process and outcomes as well as describing some of the challenges faced and overcome.