A method of ad hoc trust delegation in human-based workflow systems using one-time access key is provided herein. The method may include the following steps: generating a unique access key to a workflow system in response to a delegation of trust to one or more users; associating the unique access key with a specified portion of a workflow within the workflow system; embedding the unique access key in a message sent to the one or more users; and providing the one or more users with a one-time access to the workflow system, such that the access is limited to the specified portion of the workflow, in response to applying the unique access key to the workflow system.