The challenges of surgery in the older person may be summed up in geriatric syndromes represented by the 5Ms: Mind, Mobility, Medications, Multicomplexity, and what Matters Most to the patient. Mind: assessing for dementia and mental capacity; delirium screening and management; depression may also impact surgical outcomes. Mobility: function is a key prognostic factor and outcome measure; falls are a preventable cause of geriatric trauma. Medications: polypharmacy may cause iatrogenic harm; medication optimisation is a beneficial intervention; pharmacological strategies for delirium reduction. Multicomplexity: frailty, sarcopenia and multimorbidity are distinct but overlapping entities best handled with a patient-centred approach. What Matters Most: patient values, shared decision-making, advance care planning and resuscitation status. Aerobic and strength exercise and protein–calorie nutrition underpin multimodal prehabilitation and the management of sarcopenia and frailty. Early mobilisation, nutrition, hydration, multimodal analgesia and promotion of gut motility are common ground between enhanced recovery after surgery (ERAS) protocols and postoperative delirium prevention and management. The complexity of the older patient is best managed within the unity of the multidisciplinary team.