This paper presents an integrated process model of use-case driven analysis and task analysis for developing interactive systems. In the process model, an analysis model is developed adopting the use-case driven approach using various UML diagrams; a use case model and its supporting scenarios are defined using the UML use case diagram and sequence diagrams respectively. Then a task model is developed projecting the analysis model from a user-centric view. Given the use case and sequence diagrams, we identify tasks, sub-tasks and user actions. A dialog model defining communication between the user and the system and also a structure for the user interface is derived from the task model. Finally, we identify user-interface components (called user-interface classes in our work) from the dialog model and these are mapped to classes in the analysis model. A user-interface prototype can be generated based on the user-interface classes and the dialogue model. In this way, we provide a process model that incorporates task analysis into the use-case driven approach for the development of interactive systems.