• Introduces the concept of retainability of occlusal features and provisional hierarchy of stability. • Considers the evidence underpinning a range of approaches to enhancing long-term stability, including behavioral and mechanical interventions. • Highlights the need for further refinement of mechanical techniques coupled with an emphasis on novel behavioral approaches Orthodontic retention has seen significant refinement in recent years with an increasing focus on developing removable retainers offering improved adaptation, comfort and longevity. Similarly, fixed retention has not been immune to change, with a range of new approaches coming into common usage. Notwithstanding this, a purely mechanical approach to retention is insufficient; patient understanding, behaviors, and commitment are critical to optimal outcomes. On the basis of high-quality clinical trials, there is convincing evidence of equivalence between fixed and removable approaches in the short term. However, some level of deterioration is known to occur on the basis of long-term evaluation irrespective of the mechanical approach used. Therefore, the final frontier in orthodontic retention may reside in developing holistic mechanical and behavioral approaches to meet the challenge of mitigating the tendency for negative occlusal change in the longer term.