The increasing use of new mobility services like car and bicycle sharing, information and communication technology results in changing use patterns. Multimodal as well as intermodal use of transport modes is increasing in importance. Multi-agent travel demand models are able to describe intermodal trips for supporting transport policy in evaluating planned measures. Such models require comprehensive information on individual (intermodal) travel behaviour. Our work describes the design of a household travel survey focusing on intermodal trips. Additionally, it discusses challenges that emerge in comparing results to traditional household travel surveys, which mainly focus on main mode.