Teamwork and technology, even as people are seeing their increased use in organizations, are becoming important components of problem-based learning in academic settings. Yet, fostering computer-assisted teamwork is complex and time consuming. Knowing how and when to intervene would prove useful. This study draws from the field of project management to explore how students commit to project goals using collective asynchronous text-based communication technology. Declarative commitments--goal-orientated public, voluntary, explicit and non-retractable messages comprised of a term, an objective and a focus--made by 34 teams during a four-phase 13-week project were analysed qualitatively and quantitatively. Qualitative results show that declarative commitments voluntarily and formally package information about project constraints into a relatively potent message about tasks, coordination and project completion. Team members' suggestions as to what should be carried out in the project and requests for help often preceded others' declarative commitments. As with persuasive communication (i.e. aimed at changing beliefs, attitudes and behaviours), declarative commitments were followed by demands for clarification, new declarative commitments, confirmations of upheld commitments and clear approvals of what was committed to. Looking at project progression from a broader perspective, quantitative analyses show that declarative commitments did partially mediate the relationship between frequencies of task issues and of task solutions. This was particularly pronounced in the mid-point of the project, but it was not the case during the initial or final phases of the project. Taken together, these results suggest that teachers can facilitate computer-assisted learning and project goal attainment by monitoring asynchronous electronic discussions, and by eliciting and structuring declarative commitments.