While multi-stakeholder partnerships are emerging as an increasingly popular approach to address grand challenges, they are not well studied or understood. Such partnerships are rife with difficulties arising from the fact that actors in the partnership have different understandings of the grand challenge based on meaning systems which have distinct and often opposing assumptions, values, and practices. Each partnership actor brings with them their individual values as well as the values and work practices of their home organization's culture, alongside the wider meaning systems present within the sectoral spaces in which each organization is situated-public, private, or nonprofit. Yet, there is little understanding of how actors in multistakeholder partnerships negotiate multi-level meaning systems to reach partnership goals. In this 16-month ethnographic study, we take up a negotiated culture perspective to holistically examine the negotiation of multi-level meaning related to a focal grand challenge in a multi-stakeholder partnership established to end homelessness in Western Canada. Based on our findings, we contribute a process model to explain the ongoing negotiation of multi-level meanings in multi-stakeholder partnerships working to address grand challenges.