The physics department at Queen's University are in the process of redesigning its upper year undergraduate lab courses using a backward design strategy. Student learning activities and course assessments are being redeveloped to align with a common set of learning objectives. In parallel to this ambitious lab curriculum redevelopment, we have been implementing design-lab experiments to increase student engagement and provide more meaningful learning experiences. Procedural-lab experiments where detailed instructions are provided to the students in the lab sessions are being replaced with design labs where the students are given opportunities to design their own experimental procedures. We have also been measuring the effectiveness of this new approach by comparing student learning with and without design-lab experience, observing students in the labs, and surveying students on their scientific attitudes and experimental strategies. I will talk about the progress that we have made and the challenges we have faced.