Polypharmacy is a significant issue for many older people, including those with frailty, and it is associated with a range of adverse effects. Therefore, it is important to address polypharmacy by optimising patients’ medicines use. Medication reviews are one of the main approaches to medicines optimisation, and various tools are available to support healthcare professionals with conducting these. Another approach is deprescribing, which can improve health outcomes for patients and may have financial benefits for healthcare organisations, but can also present various challenges. This article, the second of two parts, explores the benefits of medicines optimisation in the form of medication reviews and deprescribing for older people with frailty and polypharmacy.