A system can only be improved if it is measured. In order to adequately measure a system, that system needs to be mapped and all key inter-nodal linkages, constraints and pathways recorded. Commercial supply chains demonstrate similar characteristics to other systems. Much has been written about mapping supply systems, where typically, the product or service is tracked from the originating source such as a raw materials supplier to the end customer of the product such as the consumer. There is however, another classification of supply system, where the payment for the product or service is not undertaken by the end consumer. This supply system is more often associated with not-for-profit (NFP) and non-government organisation (NGO) activities and little has been written concerning the mapping of these atypical supply systems. This is unfortunate, as it is often these types of networks that are most assumed to be inefficient and lacking appropriate quality measures. This paper discusses the characteristics of atypical supply networks and also describes a method of mapping them by using an auditing approach based on tracking funding through the system and not the flow of products or services within it. We argue that this approach is robust, because it enables the actual flow patterns within the network to be identified and not confused with, often, conflicting demands placed on atypical supply networks by the multiple stakeholders often associated with them.