Adherence to asthma medications presents a problem in all age groups, and older people with chronic illnesses such as asthma also have multiple comorbidities and consequently complex healthcare needs. It has been suggested that older people are also less likely to adhere to medication and treatment than younger people. Although the prevalence of asthma in older people is similar to that of the general population, over two-thirds of those who die from asthma are >50 years of age and there is strong evidence for under-diagnosis. Clinicians therefore face specific challenges in providing healthcare with respect to both asthma diagnosis and treatment in older age groups. Non-adherence to medication can be defined as either 'intentional' or 'unintentional'. Unintentional non-adherence is more likely to be associated with sociodemographic or physical barriers to the use of medication. Intentional non-adherence results from the balance of individual reasoning of risks versus the benefits of taking medication and acceptance of asthma diagnosis. Intentional non-adherence can be addressed through strategies that influence health beliefs and concerns about the adverse effects of medicine. Unintentional adherence can be addressed by assessing and educating the patient in relation to device use and providing education and clear written instructions about medication requirements. However, some barriers to medication use, such as financial ones, may be systematic. Most studies of medication use, efficacy, adverse effects and adherence in patients with asthma primarily involve younger people. Studies of strategies to improve asthma adherence outcomes specifically in older people are urgently needed.