The notion of managing resources in partnership flourishes in natural resources literature. The terms partnership, collaboration, and co-management are associated with co-operative environmental management. Examining issues of definition reveals similarities, differences and, at times, imprecise use of the three terms. The potential for clarity prompts the proposal of a multi-dimensional model of co-operative environmental management. The model consists of three key dimensions. The first dimension reflects the extent power is shared among the actors and agencies involved in the agreement. The second dimension delineates who is involved in the management regime. Process, the final dimension, reflects the variety of ways in which co-management may function or proceed. The presented model highlights dimensions requiring attention by those working within co-operative environmental management. The model is valuable as it reflects the complexity and range of such arrangements in practice.