The results of these two analyses demonstrated that, if key informants were carefully chosen, they could provide sufficiently high-quality data that represents community (dis)organizational processes. Under the condition of a careful selection of key informants, it was thought highly plausible that insight could be gained into social phenomena that were not measured or were only very selectively measured by the use of official data. The role of community (dis)organizational processes is a major issue in contemporary criminology causing researchers to be increasingly eager to measure community-level social mechanisms such as social trust and disorder. This paper discusses the use of expert key informants as an alternative method of measuring community processes. It contributes to the measurement of social processes at local levels by generating empirical evidence of the potential of the technique of 'key informant analyses' as an ecologically reliable and valid tool in quantitative community research. The utility of the key informant technique was explored in two different urban settings in Belgium. Tables, appendix, and references