Audio computer-assisted self-interviewing (ACASI) is a technology used to conduct statistical surveys where the computer reads questions to the respondent who can then respond by clicking appropriate answer choices on the screen. Often touch-screen interfaces are used to enhance data collection. ACASI techniques have several advantages over traditional data collection methods, including greater confidentiality, less reliance on the respondent�s reading ability and support for multiple languages. Typically, ACASI systems are deployed on touch-screen laptops; however these systems are limited by both their bulk and power consumption. ACASI is a well-established data collection methodology, however, current systems do not operate effectively on mobile devices. This project will develop an ACASI system for Windows-based handheld devices. There are currently no handheld-based ACASI systems on the market; therefore the project would represent a significant move forward in the data collection field. The PocketACASI software will be built on the latest object-oriented techniques, with questionnaires being defined by a unique XML vocabulary. The devices will be updatable via XML Web service. The project would utilize key concepts from several modules including Object-oriented programming, XML Web applications, Security engineering and databases.