Mastery learning is an educational approach (originating in the 1920s) requiring students to demonstrate mastery on assessment before they advance to the next level. Two formal models were established in the 1960s: Bloom's Mastery Learning and Keller' Personalized Systems of instruction. 

Bloom's Mastery Learning supports individualized learning by prioritizing clear, sequenced objectives supplemented by frequent assessments for learners to demonstrate mastery. In practice, it is grounded in teacher directed lessons with students moving through the curriculum at a uniform pace. If students fail assessments they are tutored and retested before they move on to new material.

Keller's Personalized Systems of Instruction supports learning with less direct teacher involvement. It is rooted in the following five components: 1) mastery of content, 2) use of proctors, 3) self-pacing, 4) stress upon the written word, and 5) use of lectures/demonstrations for motivation. Students typically advance at their own pace; if they fail assessments they study and retake those assessments until they earn passing scores.

Reassessment, which is central to both mastery learning approaches, also serves as a foundational component to proficiency-based and competency-based instructional approaches.