Systems and methods for managing and performing oilfield operations for an oilfield having geological formations and reservoirs therein are disclosed. The systems and methods provide a graphical user interface that allows a user to graphically define, edit, and automatically run a workflow for managing and performing oilfield operations. Lines are used in the workflow to express both execution flow and data flow. In this way, both execution flow and data flow may be represented in a single workflow diagram. The workflow management systems and methods also allow users to dynamically modify the workflow to add contact information for one or more other users to at least one work step. Users may then use the workflow management systems and methods to suspend running of the workflow at any modified work step and request consultation, collaboration, and/or approval from the other users whose contact information was added to the work step.