This paper presents HierTOD, a hierarchical, goal-based task-oriented dialog system that supports complex tasks in enterprise environments. Unlike existing TOD systems with a single-layer workflow structure, HierTOD utilizes hierarchical goals to support complex workflows. It provides efficient task support through components such as natural language understanding, complex goal retrieval, dialogue management, and response generation, as well as data services equipped with a domain knowledge base and search engine. It integrates two TOD paradigms: slot filling and step-by-step guidance. The effectiveness and usability of HierTOD were verified through user research.