This is an exploratory study investigating the use of wikis in academic libraries. Reasons for using and not using wikis, level of control exerted on wikis users and perceived benefits and costs of using wikis are the major areas examined. Sixty universities were selected to complete either survey 1 or survey 2, depending on their usage of wikis at the time the study was conducted. Telephone interviews were conducted for those libraries from whom there were no email replies. The response rate reached 80%. Sixteen (33.3%) used wikis for work, four (8.3%) used wikis in experimental stages, 13 (27.1%) were potential users who planned to use wikis and 15 (31.3%) did not plan to use wikis at all. The advantageous features of wikis were found to be the main reasons for their use. MediaWiki is the most commonly adopted wiki software in university libraries, and the level of control is closely related to the reasons for wiki use. Despite the fact that costs are incurred in creating wikis, current users found that the benefits outweigh the costs. It is hoped that this study can provide insights for making informed decisions in applying wikis in academic libraries. (Contains 7 tables.)