This article contextualises and presents to the academic community the full dataset of the Isan Culture Maintenance and Revitalisation Programme's (ICMRP) multilingual signage survey. The ICMRP is a four-year European Union co-sponsored project in Northeast Thailand. This article focuses on one aspect of the project, four surveys each of 1,500 participants regarding attitudes towards multilingual Thai-Isan (Thai Lao)-English signage in municipal areas in Khon Kaen Province, which have already led to the installation of some permanent signs, together with one follow-up survey. The survey data also include information on self-reported ability in Thai Lao and on frequency of usage and domain usage. It is the largest survey of this nature in Thailand and reveals a population which appears to approve of the installation of multilingual signage. However, Thai Lao identity is an especially sensitive issue following the 2014 coup, and the local population, municipalities, and academic institutions have come under heavy scrutiny by the Thai military government, which may have affected survey results. [For Part I of this study, see EJ1023991.]