Laboratories are generally regarded as critical to engineering education, and yet educational institutions face significant challenges in developing and maintaining high-quality laboratory facilities. Remote laboratories are increasingly being explored as a partial solution to this challenge, with research showing that--for the right learning outcomes--they can be viable adjuncts or alternatives to conventional hands-on laboratories. One consequential opportunity arising from the inherent support for distributed access is the possibility of cross-institutional shared facilities. While both technical feasibility and pedagogic implications of remote laboratories have been well studied within the literature, the organisational and logistical issues associated with shared facilities have received limited consideration. This paper uses an existing national-scale laboratory sharing initiative, along with a related survey and laboratory sharing data, to analyse a range of factors that can affect engagement in laboratory sharing. The paper also discusses the implications for supporting ongoing laboratory sharing.