The metaphor of the water information gap is used to describe the discontent between information users and information producers about the use of and need for specific information. This paper describes the rugby-ball methodology for specification of information needs that was developed on the basis of an analysis of the water information gap and insights from the literature on policy- and decision-analysis, problem-structuring, and information management. The methodology consists of a process-architecture to manage the process of assessing information needs and a structure to organise the information needs related to water policy objectives. The methodology was developed and enhanced through a Reflection-in-Action process in which interaction between ideas and practice leads to improved results. The paper describes the methodology and its development, and concludes both on the development process and on the abilities of the methodology to narrow the water information gap.