Execution of business processes often requires resources, the use of which is usually subject to constraints. In this paper, we study the compliance of business processes with resource usage policies. To this end, we relate the execution of a business process to its resource requirements in terms of resources consumed, produced or blocked by tasks of the business process. Policies specifying constraints on resource usage are specified in the form of obligations and the verification of whether a business process complies with a given resource usage policy is formally studied