This paper introduces and tests a conjoint choice experiment approach to modeling urban tourists' choice of activity packages. The joint logit model is introduced as a tool to model choices between combinations of activities and an experimental design approach is proposed that includes attributes from multiple alternatives as well as interactions between attributes of different alternatives. Tests for possible differences in parameter values for attributes when introduced in different parts of the day are also supported. The proposed approach was implemented and tested in a case study on Dutch urban tourists' choices of activity packages for a weekend in Paris. Shopping and sightseeing were the activities evaluated most positively. A number of significant interactions between choices of activities for different parts of the weekend was observed, with a general preference for variation in activities, and no significant interactions between choices of evening and daytime activities. It was found that respondents in the case study did not evaluate activities differently depending on the period of the weekend in which they were introduced.