W-ReTuDiS is a web-based open learner modeling system designed to support tutorial dialogue through reflective learning. It models human diagnosis of learner’s cognitive profile and constructs the learner model of historical text comprehension. The learner model is open for inspection, discussion and negotiation. The system promotes learners’ personalized reflection through tutorial dialogue, helps learners to be aware of their reasoning and leads them towards scientific thought. The system offers a two level open interactive environment: learner level and tutor level. In learner level, the learner participates in the construction of his learner model through dialogue activities, which promote reflective learning. In tutor level, the tutor based on the learner model makes decisions concerning the appropriate activity, reflective dialogue and dialogue strategy for the learner.