Accurate diagnosis of MIC failures in technical, industrial or infrastructural equipment and facilities is a grand problem due to simultaneous occurrence of other environmental factors such as aquatic biota, chemistry and physical properties of water (e.g. pH, temperature, salinity), atmospheric fluctuations (e.g. humidity and light), and the presence of other corrosive agents. Even though the acceleration of corrosion processes by the direct and indirect influence of microbes is clearly documented in case studies and in the literature, many incidences are not thoroughly investigated due to the lack of adequate sampling and analysis procedures. The aim of this WG is to establish a guideline for sampling, analysis and metadata (i.e. information about the source of the data, environmental parameters and sampling procedures) collection that will be made available on the COST Action webpage and communicated in relevant dissemination platforms such as conferences, technical and peer-reviewed publications. To advance the MIC research agenda for diagnostic methods, members of WG2 will work together to address the defined knowledge and technology gaps in joint project applications to substantiate the implementation of the research agenda devised in the COST Action.