CIAIR, Nagoya University, has been compiling an in-car speech database since 1999. This paper reports on various characteristics of the database. We have developed a system called the Data Collection Vehicle (DCV), which supports synchronous recording of multichannel audio data from 16 microphones that can be placed in flexible positions, multi-channel video data from 3 cameras, and vehicle-related data. In the compilation process, each subject had conversations with three types of dialogue system: a human, the "Wizard of OZ" system, and a conversational system. In this paper, we present the specifications and the characteristics of the database.