The data collected is based on the answers of 56 respondents to an online questionnaire carried out among a diverse population of stakeholders within GreyNet International, the Grey Literature Network Service. The dataset consists of responses to ten questions, the last of which is open ended and all of which allow for additional comments. The first nine questions deal with the uses, applications, and opinions related to persistent identifiers. Eight of the questions deal with the DOI and one pertains to the ORCiD or other types of researcher ID. The data was collected in the second quarter of 2019 via SurveyMonkey, where it remains stored along with a copy housed in the DANS Easy Archive.