Theories of self-regulated learning assume that learners flexibly adapt their learning process to external task demands and that this is positively related to performance. In this study, university students (n = 119) solved three tasks that greatly differed in complexity. Their learning processes were captured in detail by task-specific questionnaires and computer-generated log files. Results indicate that students adapted almost all learning processes significantly to task complexity. For example, students accessed more hypertext pages for complex tasks than for simple tasks. However, this kind of adaptation was not consistently related to performance. For variables capturing learners' self-regulation, such as the number of accessed hypertext pages, more pronounced adaptation was significantly and positively related to performance even when learners' general processing depth was statistically controlled. Results were less consistent for variables capturing learners' self-monitoring, such as their judged task complexity. (Contains 3 tables and 2 figures.)