Vortex is a work ow language to support decision making activities. It centers around gathering and computing attributes of input objects. The semantics of Vortex is declarative, and the dependency graphs of Vortex programs are acyclic. This paper discusses the application of symbolic model checking techniques to veri cation of Vortex programs. As a case study we used a Vortex program MIHU for online customer support. The control structure and the declarative semantics of Vortex programs enabled us to develop various optimization techniques for the purpose of verification. These techniques include constructing a disjunctive transition BDD, variable pruning, projection of initial constraints, and predicate abstraction.